Reddell et al. (2020) Christmas Island vegetation surveys

Anja Zimmermann; Paul Reddell; Anthony R Milnes

Comprehensive surveys and mapping of the vegetation on a number of areas selected for possible future mining of phosphate on Christmas Island, Indian Ocean, in concert with an evaluation of its ecology, enabled an assessment of potential impacts of disturbance. The research targeted the possible impacts on forest types as well as on the occurrence and distribution of EPBC-listed and other significant flora. Mining has not proceeded but the unique dataset provides new information on the floral ecology on this isolated seamount, demonstrates the effectiveness of a rigorous strategy for establishing baseline conditions, and informs practical approaches for both protecting significant flora and re-establishing key revegetation types in areas of significant land disturbance.

July 2020 Christmas Island vegetation surveys Information for this paper was extracted from: Main Report & Technical Appendix F in Phosphate Resources Limited Draft Environmental Impact Statement for the proposed Christmas Island Phosphate Mines (9 sites). EPBC 2001/487. November 2005. (EIS prepared by EWL Sciences P/L & Tallegalla Consultants P/L; edited by A R Milnes & D Gillespie). The research was undertaken by P Reddell, A R Milnes & A Zimmermann from EWL Sciences P/L. Vegetation surveys to assess possible impacts of phosphate mining, Christmas Island, Indian Ocean P ReddellA, A ZimmermannB and AR MilnesC A Ecobiotics P/L, Yungaburra Office, 7 Penda Street, Yungaburra 4884, Queensland, Australia 5 Banyan Street, Fannie Bay NT 0820 C Earth Sciences, The University of Adelaide, SA 5000. B Abstract __________________________________________________________________ 2 Introduction ______________________________________________________________ 2 Survey methods ____________________________________________________________ 2 Site reconnaissance _______________________________________________________________ Strategic transects ________________________________________________________________ Intensive survey plots _____________________________________________________________ Targeted surveys for endangered, vulnerable or rare species ____________________________ 3 3 4 4 Results ___________________________________________________________________ 7 Mapping of vegetation types in the areas selected for possible future mining _______________ 7 Floristic and structural descriptions of the vegetation types______________________________ 8 Distribution and population data for species of conservation significance _________________ 10 Threatened and endemic flora _____________________________________________________ 11 Plant species listed under the EPBC Act _____________________________________________ 11 Asplenium listeri __________________________________________________________________________11 Tectaria devexa var minor ___________________________________________________________________12 Carmona retusa ___________________________________________________________________________12 Other plant species proposed as endangered or vulnerable _____________________________ 13 Species proposed as rare or poorly-known ___________________________________________ 14 Endemic species _________________________________________________________________ 15 Assessment of potential impacts of mining _____________________________________ 15 General overview ________________________________________________________________ 15 Potential impacts on vegetation type ________________________________________________ 17 Impacts on EPBC-listed and other significant flora____________________________________ 17 Species listed under the EPBC Act ____________________________________________________________18 Asplenium listeri _________________________________________________________________________ 18 Tectaria devexa var minor __________________________________________________________________ 18 Carmona retusa __________________________________________________________________________ 19 Pneumatopteris truncata ___________________________________________________________________ 20 Other plant species proposed endangered or vulnerable ____________________________________________20 Species proposed as poorly-known or rare ______________________________________________________20 Endemic species __________________________________________________________________________23 Summary ________________________________________________________________ 23 Acknowledgements ________________________________________________________ 24 Page 1 of 76 July 2020 Christmas Island vegetation surveys Acknowledgements ________________________________________________________ 24 References _______________________________________________________________ 24 Abstract Comprehensive surveys and mapping of the vegetation on a number of areas selected for possible future mining of phosphate on Christmas Island, Indian Ocean, in concert with an evaluation of its ecology, enabled an assessment of potential impacts of disturbance. The research targeted the possible impacts on forest types as well as on the occurrence and distribution of EPBC-listed and other significant flora. Mining has not proceeded but the unique dataset provides new information on the floral ecology on this isolated seamount, demonstrates the effectiveness of a rigorous strategy for establishing baseline conditions, and informs practical approaches for both protecting significant flora and re-establishing key revegetation types in areas of significant land disturbance. Introduction Reddell et al. (2019) described the floral ecology of Christmas Island (Fig. 1) as a basis for generating an effective approach to sustainable rehabilitation of areas mined for phosphate over more than 100 years. They noted that there were records of about 420 species of vascular plants, of which approximately 242 species were indigenous to the Island and a further 177 species had been naturalised since human occupation. Natural vegetation varies from tropical rainforest with 50m tall emergent trees through to low shrublands on exposed coastal sites (Fig. 2). Fernlands, shrublands and secondary regrowth forests currently occupy sites disturbed by human activities. In the early 2000’s, Phosphate Resources NL (PRL) submitted a proposal to the Australian Government to expand phosphate mining into a number of new areas. As part of this proposal, detailed vegetation and other surveys of the selected new areas and adjacent sites were commissioned to form the basis for assessing impacts of possible future mining operations. Mining did not subsequently proceed but the new survey plan and data on flora ecology and distribution stand as an important addition to knowledge of the Island’s vegetation and contribute to strategies for effective mine rehabilitation. Survey methods PRL had identified nine areas of vacant Crown land on the Island (Fig. 3) with economically viable reserves of phosphate. The vegetation in the nine areas and their surrounds was surveyed over an intensive three-week period in March 2003. Two ecologists were responsible for the design and implementation of the survey in the field and for all detailed observations, record keeping, species identifications and data analysis and interpretation. Local support staff assisted in establishing plots, measuring tree sizes and pressing plant specimens. The vegetation survey had four broad components: Page 2 of 76 July 2020 Christmas Island vegetation surveys 1. an initial site reconnaissance and inspection of each of the nine areas and their immediate surrounds; 2. establishment of strategic transects to describe the species present and the structure and composition of the main vegetation types in each area; 3. detailed measurements of species numbers, size class distributions and structural features in intensive survey plots representative of the range of vegetation types in each area; and, 4. focussed surveys of specific environments, habitats and locations in, or immediately adjacent to each of nine areas for significant flora (endangered, vulnerable and rare species) that could be impacted by mining. Site reconnaissance Prior to finalising the design and location of the three more detailed components of the vegetation survey, all of the nine selected areas were inspected to overview their physical features and terrain and the main vegetation types and species present. Particular attention was paid to the relationship between vegetation type and substrate and/or site topography and, as a consequence, how closely vegetation type reflected the suitability and likelihood of mining in particular parts of the areas. The observations from this initial site reconnaissance were then used to assist in interpreting aerial photography and satellite imagery from which the siting of the strategic transects was decided. These observations were also used to reduce the intensity of sampling in parts of the nine selected that would not be mined because they had little or no phosphate resource present or were on or near steep and inaccessible slopes. On this basis, some areas were sampled at a much lower intensity than in the more detailed vegetation survey activities (although some transects and plots were located in these areas to confirm our preliminary assessment and to provide background and ‘contextual’ information on the vegetation types that were present). Strategic transects The purpose of the strategic transects was to (a) record the range of plant species present in each of the nine selected areas and (b) identify and describe the major forest structural types, their variability and heterogeneity, their relationship to landscape position and site conditions (e.g. soil depth, outcropping of limestone, exposure to strong winds, etc) and features relevant to providing habitat for fauna. This information underpins, in part, our ecological interpretation of the distribution of forest types on Christmas Island (Reddell et al. 2019). These latter vegetation-landscape relationships also provide a strong basis on which to assess parts of the nine selected areas that were likely to be explored for phosphate resources, with the presence of evergreen closed forest being a strong surrogate for potentially economic phosphate ore. The locations of strategic transects are shown in Figures 4 to 6. Detailed notes were taken on Page 3 of 76 July 2020 Christmas Island vegetation surveys features of the vegetation types, soils and landforms along the transects together with the species present, including the occurrence of any weeds. The specific locations where any species listed in the Australian Government’s Environment Protection Biodiversity Conservation Act 1999 (EPBC Act) were encountered were recorded, as were those for a further 8 species recommended for listing under the EPBC Act (Holmes and Holmes 2002). An inventory of all plant species within a 10m wide strip along the length of each individual transect was made. Representative specimens of plants that could not be identified in the field were collected for later taxonomic determination. The strategic transects covered a total of slightly more than 31 ha and, although varying between areas, the data recorded represented a complete inventory of plant species on 8% of the total of the nine selected areas (see Table 1). Intensive survey plots Thirty-five detailed survey plots (Figs 4 to 6) were established to characterise and quantify the structural features and floristic composition (e.g. height, basal area, stem densities, size class distribution, crown and foliage cover, stratification, canopy architecture, litter cover, species compositions) of the major natural forest types in each of the selected areas. In general, these plots were 20m x 20m in size but at 7 sites were of slightly different dimensions in order to accommodate specific site features. A further 10 plots (3 in selected areas and 7 outside) were established in secondary vegetation of varying ages that had established naturally on formerly cleared sites. All trees with a diameter at breast height (DBH) of greater than 5 cm were identified and measured in these plots, while counts of saplings of each species were also made. Estimates of seedling densities in the plots were obtained from two 5 x 5 m subplots established in each main plot. A wide range of habitat and structural features of the sites were recorded. Heights of canopy and emergent trees were estimated visually with the aid of a rangefinder. The presence of more cryptic epiphytes on the sites was determined by scanning the canopy and upper branches with binoculars and by searching the forest floor for flowers, leaves or other evidence of their presence. In addition to the quantitative data from these plots, lists of all species occurring in an additional 10m wide strip surrounding each plot were also made. The quantitative data from these survey plots represented a total of approximately 1.5 ha of the selected areas, while the species occurrence data was from 6 ha (i.e. 38 plots of ~40m x 40m). Targeted surveys for endangered, vulnerable or rare species Targeted surveys were designed to collect additional data on the presence and distribution of populations of endangered, vulnerable and rare plant species which, together with that from the transects and the intensive plots, could be used to assess the possible impact of mining operations on these taxa. When planning these surveys, areas in the selected sites that would not be mined (or not Page 4 of 76 July 2020 Christmas Island vegetation surveys be impacted by mining) because of topography and/or limited phosphate resource were excluded. The targeted surveys gave highest priority to two species groups: 1. The four EPBC-listed species at the time: Asplenium listeri (Aspleniaceae), Pneumatopteris truncata (Thelypteridaceae), Tectaria devexa var minor (Dryopteridaceae) and Carmona retusa (Boraginaceae); 2. Eight species suggested as endangered or vulnerable (and recommended for priority consideration of EPBC-listing; Holmes and Holmes 2002). These are: • Endangered - Asystasia alba (Acanthaceae), Blumea lanceolaria (Asteraceae), Dicliptera maclearii (Acanthaceae) and Muellerargia timorensis (Cucurbitaceae) • Vulnerable - Cycas rumphii (Cycadaceae), Dendrocnide peltata var murrayana (Urticaceae) and Spondias cytherea (Anarcardiaceae). Search strategies were designed on the basis of the presence of ‘potential habitat’ for individual species. ‘Potential habitat’ for these species was defined from their currently known distributions and an understanding of their likely environmental requirements (as briefly summarised in Tables 2 and 3). Note that ‘potential habitat’ only implies that the environmental conditions were consistent with the species habitat in known distributions on the Island and elsewhere. ‘Potential habitat’ does not necessarily imply that the species should be encountered in these areas as other proximal and contingent factors also determine species distributions. Four broad potential habitat types were identified for the species as follows: 1. Cliffs and limestone outcrops: Asplenium listeria* and Dendrocnide peltata var murrayana. 2. Deciduous vine thicket (DVT) and gaps and edges in semi deciduous mesophyll vine forest (SDMVF): Carmona retusa*, Asystasia alba, Dicliptera maclearii, Muellerargia timorensis, Cycas rumphii and Dendrocnide peltata var murrayana. 3. Semi deciduous mesophyll vine forest (SDMVF): Spondias cytherea. 4. Evergreen closed forest (ECF): Tectaria devexa var minor* and Blumea lanceolaria. No search strategy was devised for the fern Pneumatopteris truncata as this species is restricted to a specialised habitat (permanently moist sites on the lower terraces associated with localised groundwater seepages over exposed basalts) that did not occur on or in proximity to the selected areas. In addition, information on the habitats and distribution of a further 44 species of conservation interest (identified in the report by Holmes and Holmes 2002) was compiled (Table 4). No specific additional survey was designed for these species, but careful note was made of their occurrence in the reconnaissance surveys, transects, plots and targeted threatened-species survey areas. These taxa comprised 33 species suggested as rare and 11 species defined as “poorly-known but possibly * Listed species under EPBC Act. Page 5 of 76 July 2020 Christmas Island vegetation surveys threatened”. The emphasis in our assessment of this third group was on the 14 ‘rare’ species and 4 ‘poorly- known’ species found in the evergreen closed forest as this is the vegetation that would have been most impacted by mining. Where potential habitats of threatened species in the nine selected areas were confined to relatively small or restricted locations, the search strategy aimed to intensively survey more than 75% of these areas (e.g. for Asplenium listeri, Asystasia alba, Dicliptera maclearii, Muellerargia timorensis, Cycas rumphii, Dendrocnide peltata var murrayana, Spondias cytherea and for primary habitat of Carmona retusa). Where potential habitat was much more widespread, the strategy was to intensively assess more than 15% of the total potential habitat area to provide a robust sample size from which to estimate likely occurrences and populations in the selected areas. In the case of one species (Carmona retusa) with a secondary habitat (i.e. in areas disturbed by previous mining), this habitat type was not intensively sampled in these surveys. The areas of secondary habitat of Carmona were small compared to its primary habitat on the Island and stem densities at these sites were comparatively low. The sampling strategy for the targeted surveys involved selection of a number of blocks of each of the four potential habitat types which were then thoroughly searched on an approximately 3m grid. The location and orientation of the blocks depended on the habitat type/target species and the site context. For Asplenium listeri, the search blocks were long, narrow and often winding strips (up to 15m wide) along the edges of limestone cliffs and on semi-exposed limestone outcrops. For the other three habitat type groups, the individual blocks were more regular shaped and between 0.375ha (75 x 50m) and 1ha (100 x 100m) depending on the selected location and its landscape context. Locations of all the blocks surveyed for threatened species are shown in Figures 7 and 8. An estimate of the area on, or in close proximity to each of the areas selected for possible future mining that was surveyed for EPBC-listed species and for those suggested as endangered, vulnerable, poorly-known or rare by Holmes and Holmes, is summarised in Table 5a. The area of each major vegetation type that was surveyed within the selected areas for threatened species is summarised in Table 5b. When endangered, vulnerable or ‘poorly-known’ species were found the number of individuals were counted, the location was recorded as accurately as possible (given that GPS readings were not possible under the forest canopy in many areas), and an even more intensive local search was conducted for further individuals (i.e. the search area in the vicinity of the recorded occurrence being doubled). The exception to this approach of increasing the search intensity around recorded individuals was for Carmona retusa which was locally common in potential habitat areas on the selected areas (as it is in similar environments elsewhere on the Island). Where species suggested as rare were encountered, only the number of individuals/discrete populations and the block in which these plants were found were recorded. Page 6 of 76 July 2020 Christmas Island vegetation surveys Results Mapping of vegetation types in the areas selected for possible future mining Based on the observations and results from the field surveys, the vegetation in each of the areas selected for possible future mining was mapped into 12 categories representing broad structural types (or groups of structural types) and the extent and severity of past anthropogenic disturbances (see Figs 9 and 10 as examples of all surveyed areas). Descriptions of the key structural and floristic features of the 12 mapping units are summarised in Table 6. Map units 1 to 7 are regrowth shrublands and secondary forests occurring in previously cleared or highly disturbed areas with the vegetation type present reflecting the intensity and/or age of the disturbance. Map unit 11 is a cleared area planted with exotic fruit and timber species in the 1980’s. Map unit 12 comprises roads and bare clearings. Map units 8, 9 and 10 are natural vegetation types that have not been extensively cleared but where localised and sometimes high-impact anthropogenic disturbances have occurred (e.g. clearing for drill lines and tracks, timber removal for construction). Three disturbance classes are mapped in these forest types, with the type of hatching on the maps indicating the spatial occurrence and likely intensity of these past disturbances (as reflected in their impacts on different strata of the forest). The three disturbance classes mapped are: 1. largely undisturbed areas with no evidence of anthropogenic activities; 2. some anthropogenic disturbance but of relatively low intensity (e.g. localised understorey clearing); 3. evidence of significant anthropogenic disturbance where one or more strata (emergents, canopy, subcanopy, and/or mid-storey and ground layer) of the forests have been affected (e.g. subcanopy removal for timber gathering). Exploration drill-lines, which are marked separately on each map, fall into this disturbance class. Note that map unit 10 is a diverse unit comprising all four structural types (mesophyll vine forest, mesophyll vine forest + Ficus, closed mesophyll vine forest, closed mesophyll vine forest + emergents) of tall evergreen closed forests. Although these four forest types are clearly distinguishable during ground surveys (e.g. based on height of canopy, presence and absence of emergents, frequency of plank buttressing, presence of Ficus, etc.) and potentially represent different habitats, they are grouped together for mapping as they could not be differentiated readily using the available aerial photography or satellite imagery and there was no other feasible method for mapping them in a spatially accurate manner (e.g. reliable GPS positions cannot be obtained under closed canopy forest). Evergreen closed forests (map unit 10) occupy approximately 79% of the areas selected for possible future mining, with much smaller areas of semi-deciduous vine forests (map unit 9) and deciduous vine thickets (map unit 8) also present (see Table 7). Most of this native vegetation has not Page 7 of 76 July 2020 Christmas Island vegetation surveys been subject to major anthropogenic disturbance. Regrowth vegetation and secondary forests in previously cleared areas, plantations of exotic trees, and roads and other bare ground comprise the remaining 16% of the selected areas (Table 7). There are substantial differences in the vegetation types present and the degree of past disturbance in individual areas selected for possible future mining (Table 8, Figs 9 and 10). Three of the four largest areas (MCI 70/8, 70/9 and 70/14) are dominated by evergreen closed forests which cover greater than 85% of the site. Less than 20% of the forest area in each individual selected area is affected by previous anthropogenic disturbance (Table 8). In contrast, the second largest area (MCI 70/10) has less than 70% of the original vegetation cover remaining, and only slightly more than onethird of this is undisturbed, the rest having localised impacts associated with drill-lines, tracks, understorey clearing and timber extraction (presumably for construction). Detailed descriptions of the disturbance status of forests in each individual selected area are provided in Table 9. Floristic and structural descriptions of the vegetation types A total of 154 species were recorded from transects, plots, survey blocks and opportunistic observations in, or immediately adjacent to, the areas selected for possible future mining. Ninety-eight of these species were native to Christmas Island and these comprised 35 trees, 22 ferns, 14 vines/scramblers, 13 shrubs, 7 orchids, 6 herbs/rushes and 1 palm. Ten of the Island’s endemic species were recorded on or in the immediate vicinity of the selected areas, together with three currently EPBC-listed species (Asplenium listeri, Carmona retusa, Tectaria devexa var minor). None of the seven species identified as endangered or vulnerable in the Holmes and Holmes (2002) report on the conservation status of Christmas Island plants were found in the selected areas, but 13 species that had been suggested as rare were identified, together with one ‘poorly-known’ species. Fifty-six species that have been naturalised on Christmas Island since settlement were also recorded in the selected areas. The majority of these occurred in disturbed areas (e.g. clearings and old minefields) and along road verges. Only three of these introduced species (Clausena excavata, Leucaena leucocephala and Turnera procumbens) were found in relatively undisturbed natural vegetation, usually as understorey or mid-stratum components in vegetation types that had strongly deciduous or semi-deciduous characteristics, but also where there was likely significant canopy damage in the past. Naturalised species comprised between 7% and 43% of the total flora in individual selected areas largely reflecting the extent of previous disturbance within, or in immediate proximity to, the particular site. Some of these naturalised species are highly invasive with potential to become environmental weeds in disturbed areas and, if not controlled, have potential to deflect and impede the development of rehabilitation. A list of all 154 species recorded during the survey of areas selected for possible future mining is presented in Table 10. To aid in the ecological interpretation of these data and to integrate it more closely to the vegetation mapping, structural descriptions and potential faunal habitats, the species are Page 8 of 76 July 2020 Christmas Island vegetation surveys listed in relation to the vegetation types in which they are found, rather than to each of the specific areas where they were recorded. An additional column in Table 10 records the occurrence of species in large tree-fall gaps and drill-lines in map unit 10 because of the extent of this type of disturbed habitat within this forest type. When collated, the species presence/absence data shows clear differences between the vegetation types in species diversity, the relative proportions of native and introduced taxa, the proportions of different lifeforms present and the actual species composition (Table 11). Quantitative floristic and structural data on different vegetation types in the areas selected for possible future mining were gathered from the 38 measurement plots established during the survey (Table 12). These plots provide representative examples of the major vegetation types. A summary of key structural features of these forest types (excluding secondary and regrowth vegetation) is presented in Table 13 and Figures 11 and 12. The data show strong trends in increasing canopy and emergent height, total basal area, and contributions of very large trees to total basal area that are associated with greater structural complexity of the forests (from DVT to SDMVF to MVF to CMVF). These trends are further illustrated by profile diagrams made for some of these plots during the field survey (Figs 13 to 16). These diagrams (based on 35m x 5m transects) use the same vertical and horizontal scales and illustrate proportion position, depth and width of individual tree canopies. Besides showing the gross structural differences between the major vegetation types, three of these diagrams (Figs 14 to 16) also illustrate the variability in forest structure and stratification, and consequently potential habitat value for the endangered Abbott’s Booby, within map unit 10. Because of (1) the very low diversity of tree species in Christmas Island’s forests, (2) the consequent broad distribution of many of these species across more than one forest type and (3) the lack, for comparative purposes, of any previous floristically-based classification of forest types on Christmas Island, a more detailed classification and ordination based on floristic composition of the plots was not undertaken as part of this study. However, a qualitative interpretation of the distribution of some prominent tree species across the gradient of vegetation structural types is included in Figure 17. The effectiveness of the survey methods in sampling the plant species on the areas selected for possible future mining is illustrated in Figure 18 by the species-area curves for the quantitative survey plot data in (a) evergreen closed forest (ECF) and (b) semi-deciduous mesophyll vine forest (SDMVF). For example, there were 22 quantitative survey plots in ECF in which species composition data was collected. Each plot comprised 0.16 ha (a 20 x 20m inner plot and a further surrounding 10m buffer in which all species were recorded) and in total these plots sampled 3.5 ha of this forest type. Fifty seven species were recorded on the 22 evergreen closed forest plots, with the number of new species added per plot diminishing very significantly after the 12th plot (~2 ha sampled, 55 species recorded). Sampling of an additional 43.7 ha of this forest type in strategic transects and threatened species surveys found only a further 8 species (the shrubs Berrya cordifolia Page 9 of 76 July 2020 Christmas Island vegetation surveys and Callicarpa longifolia; the lithophytic herb Procris pedunculata; the ground ferns Leptochilus decurrens, Pteris tripartita, Pteridrys syrmatica and Tectaria devexa; and the epiphytic orchid Thrixspermum carinatifolium). In the SDMVF, 62 species where found in the 9 quantitative survey plots (1.4 ha) while a further 11 species were found in the transects and threatened species surveys (a further 1.3 ha). Distribution and population data for species of conservation significance We have summarised Holmes and Holmes (2002) data from 405 sites in relation to species distributions and populations across the Island, and species occurrences in, or in close proximity to, the areas selected for possible future mining. We divided the Island into four sectors: Western, Central, Northeastern and Southeastern (Fig. 19). We then plotted the Holmes and Holmes sites within each sector in relation to vegetation type from the Mitchell (1985) map in the Christmas Island GIS (Table 14a) to examine: • the comparative intensity and representativeness of sampling of different vegetation types across the Island; • the distribution and population of species of conservation significance in sites in the different sectors of the Island; and, • the occurrence and population of species of conservation significance on, or within 100m of, the selected areas. Of the 405 sites surveyed by Holmes and Holmes, most (217 sites) were in closed forests on shallow soils or scree slopes (Table 14b), while the highest intensity of sampling (i.e. the greatest number of sites per 100 ha of a particular vegetation type) was in the vine woodlands, the heaths and the closed forests on freshwater seepages (Table 14c) that comprise less than 5% of the Island’s total land area. Vegetation types in the Western and Central areas of the Island were also sampled at higher intensities than those in the Northeast and Southeast (Table 14c), probably reflecting a strategy to sample the areas of the Island that in general were less studied floristically. About 25% (101) of the Holmes and Holmes sites were in the tall closed forest on deep soil, the vegetation type in Mitchell’s classification that has been most impacted by former phosphate mining (Table 14b) and which is fully subsumed within our evergreen closed forest mapping (ECF) unit. The occurrence across the Island and the number of sites and number of individuals of species of conservation significance from Holmes and Holmes’ data is summarised in Table 15. The number of species of conservation interest recorded in the Western, Central, Northeastern and Southeastern areas of the Island are 20, 16, 14 and 17 respectively. From the GPS co-ordinates provided in the Holmes and Holmes data, 19 of their sites fell within the boundaries of four of the areas selected for possible future mining on which our study was focussed, while a further 13 were within 100m of the boundaries of five of these areas (Table 16a). Page 10 of 76 July 2020 Christmas Island vegetation surveys Thirteen species of conservation significance occurred in, or close to, the selected areas with the number of sites and the number of individuals recorded for these species presented in Table 16b. The data is consistent with that found in our surveys. All of the species found by Holmes and Holmes on the areas selected for possible future mining were found on these same areas in our surveys. Our surveys, because of their higher local intensity of sampling, also found seven additional species of conservation significance not recorded from Holmes and Holmes sites in these specific areas. Threatened and endemic flora Information on the occurrence of threatened and endemic flora of Christmas Island on, or in close proximity to, the selected areas was gathered from the transects, quantitative plots and targeted surveys, together with the site data from Holmes and Holmes’ Island-wide surveys. From our data and that of Holmes and Holmes, 14 species of significant flora were found on the areas selected for possible future mining. These comprised 2 EPBC-listed species (Tectaria devexa var minor and Carmona retusa), 1 poorly-known taxon (Blumea balsamifera) and 11 rare species (the endemics Colubrina pedunculata, Flickeringeria nativitatas, Grewia insularis and Phreatia listeri plus Amaracarpus pubescens, Bryobium pubescens, Ficus saxifolia, Leptochilus decurrens, Pteridrys syrmatica, Tectaria dissecta and Thixspermum carinatifolia). A further 7 species of significant flora were found in close proximity to one or more of the selected areas. These taxa comprised the EPBC-listed fern Asplenium listeri, 2 vulnerable species (Cycas rumphii and Spondias cytherea), 3 rare species (Abuliton listeri, Leucas zeylandica and Strongylodon lucidus) and 1 poorly known species (Tectaria sp.). A total of 11 endemic species were recorded on, or near to, the selected areas. These were Abuliton listeri, Arenga listeri, Asplenium listeri, Brachypeza archytas, Colubrina pedunculata, Flickeringeria nativitatas, Grewia insularis, Hoya aldrichii, Pandanus christmatensis, Pandanus elatus and Phreatia listeri. Plant species listed under the EPBC Act Populations of three Christmas Island plant species that were listed as endangered or vulnerable under the EPBC Act (Asplenium listeri, Tectaria devexa and Carmona retusa) were located within, or in close proximity to, the areas selected for possible future mining. The EPBC-listed fern Pneumatopteris truncata was not found on, or in the immediate vicinity of, any of the selected areas. This was not unexpected considering its specific habitat requirements which restrict its distribution to localised groundwater seepages and permanently moist sites (usually on the mid to lower terraces and associated with exposed basalt) Asplenium listeri A single population of the endemic, lithophytic fern Asplenium listeri (Aspleniaceae) that is Page 11 of 76 July 2020 Christmas Island vegetation surveys EPBC-listed as endangered was found on a south-easterly exposure of limestone cliff just to the east of area MCI 70/12 (Fig. 20a). This site is typical of the habitat of this species elsewhere on the east coast of the Island. Despite an extensive search of most of the potential habitat (see Figs 7 and 8) in this and the only other site in the vicinity of the selected areas with similar limestone cliff habitat (to the east of MCI 70/8), no further populations were found. Holmes and Holmes recorded 2 populations of this species in the northeast of the Island, but both were more than 2 km to the south of the location near MCI 70/12. They reported no populations of this species in the southeast of the Island near MCI 70/8. Their re- assessment of the conservation status of the flora of Christmas Island (Holmes and Holmes 2002) strongly supports the retention of the endangered status of this species. Tectaria devexa var minor A single individual of the ground fern Tectaria devexa var minor (Dryopteridaceae) that was EPBC-listed as endangered was found in a tree-fall gap next to an old drill-line through complex mesophyll vine forest in the south-eastern corner of area MCI 70/8 (Fig. 20b). Despite its often colonial nature (i.e. occurrence in groups), a more intensive search in the vicinity failed to locate other individuals of this species. Although significant areas with similar environmental conditions in this and other selected sites were traversed and assessed extensively during the flora survey, no other individuals of T. devexa were found. Advice provided at the time of the flora survey by a Parks Australia North botanist on Christmas Island was that the Holmes and Holmes conservation status survey of Christmas Island’s flora conducted in 2002 had not located any populations of T. devexa in the areas selected for possible future mining. However, six individuals where found immediately to the south of MCI 70/8 within 500m of the location of our record. Our estimate of this location was based on the GPS co-ordinates in confidential data from the Holmes and Holmes report. The most recent assessment of the conservation status on the Island of this variety of Tectaria devexa (Holmes and Holmes 2002) suggests that it should be considered rare based on the location of more than 400 individuals in evergreen closed forest, approximately 90% of which occurred in the west of the Island (Table 15). This contrasts with the current EPBC status of the species as endangered. This current endangered status is likely to be based on the conservation requirements for the small remnant population of another variety of T. devexa which is found in a karstic landscape at Mt Etna in Queensland and with which Tectaria devexa var minor is jointly listed. Carmona retusa The shrub Carmona retusa (Boraginaceae) was found in high numbers in its primary habitat (deciduous vine thickets and drier more open areas of semi-deciduous mesophyll vine forest) in three of the areas selected for possible future mining in the northeast of the Island. We also found it, and would expect it to have a scattered occurrence, in areas of secondary habitat (forest regrowth on stockpiles and edges) that were not covered by the targeted surveys for threatened species. Page 12 of 76 July 2020 Christmas Island vegetation surveys In one of the selected areas (MCI 70/13), it was an extremely common component in more open areas between clumps of trees in semi-deciduous mesophyll vine forest on a wind-exposed, easterly facing slope. Carmona was present in all three measurement plots and in the two focussed survey plots that were established here. On these plots it had an average density of 2730 stems per ha (range 900 to 4350 stems per ha). C. retusa also occurred in the plot established in the DVT in site MCI 70/11 (an area that is unsuitable for mining) where it was present at an estimated density of around 1300 stems per ha. A few scattered individuals were also present in the shrubland-secondary forest mosaic in this area. Individuals of Carmona were recorded scattered through secondary regrowth forest on old mine stockpiles along the western edge of site MCI 70/12. Away from the proposed areas selected for possible future mining, we observed Carmona as a widespread and common shrub in these same vegetation types elsewhere on the north-eastern terraces of the Island. This species was not included in the consultancy report by Holmes and Holmes (2002) because of its widespread distribution on terraces around the Island, particularly in the north-west. These authors did not consider it to fall into any of the threatened categories under Rare or Threatened Australian Plant (ROTAP) guidelines (Briggs and Leigh 1995). The original EPBC listing of this species appears to relate solely to its status in Queensland (where it is scheduled under that State’s Nature Conservation Act) rather than necessarily reflecting its conservation status on Christmas Island. Carmona retusa has a wide distribution in the tropical Asia-Pacific region occurring from India to the Philippines, Papua New Guinea and the Solomon Islands (Barker and Telford 1993). It also occurs in and on the edges of vine thickets on Cape York Peninsula, the region for which it was EPBC-listed. We understand that based on new information on the extent of its distribution and populations on Cape York, the EPBC-status of this species is under review. Other plant species proposed as endangered or vulnerable No individuals of any of the 7 species considered endangered or vulnerable (and recommended for EPBC-listing) by Holmes and Holmes were found on the areas selected for possible future mining during our survey. This is not surprising as very little habitat for most of these species occurs in these areas (Table 3). Six of the species (Asystasia alba, Dicliptera maclearii, Muellerargia timorensis, Cycas rumphii, Dendrocnide peltata var murrayana and Spondias cytherea) typically occur on relatively shallow soils in, or on the fringes of, drier SDMVF and DVT vegetation on the Island’s terraces. Only the herb Blumea lanceolaria occurs in evergreen closed forest habitats where it is found on the edges of openings and along abandoned exploration drill-lines. However, this species has, to date, only been recorded from sites on the western half of the Island well away from any of the selected areas (Du Puy 1993; Holmes and Holmes 2002). We did observe two of the suggested vulnerable species during our survey, but both were outside the mineable area of the selected sites. Single mature individuals of Cycas rumphii and Spondias cytherea were found close to the eastern and southeastern boundaries of MCI 70/11. Holmes and Page 13 of 76 July 2020 Christmas Island vegetation surveys Holmes found a population of 11 individuals of Spondias in a location very close to our record near MCI 70/11, but they record no other proposed endangered or vulnerable species at sites in proximity to any of the selected areas. Species proposed as rare or poorly-known Only one of the 11 ‘poorly-known’ species (Blumea balsamifera) was recorded in our surveys of the areas selected for possible future mining. A single individual of this herbaceous shrub was found in an area of secondary regrowth on transect 9E in the northern end of MCI 70/9, while two other individuals were found in regrowth on the edge of an old minefield just north of this proposed site. Single individuals of a second ‘poorly known’ species, Tectaria sp. (formerly T. siifolia) were recorded in abandoned minefields near two of the selected areas (edge of minefield west of MCI 70/8; edge of minefield south of MCI 70/14). Holmes and Holmes found none of the ‘poorly known’ species on their sites that were on, or in proximity to, the selected areas. Of the 33 species suggested as rare by Holmes and Holmes (2002), 12 were found on the selected areas in our surveys. These comprised: • 4 endemic species - the orchids Flickeringia nativitatis and Phreatia listeri that are common throughout the closed evergreen forests of the Island (Table 15), and the small trees Colubrina pedunculata and Grewia insularis that occur on shallow soil profiles in dry semideciduous mesophyll vine forest and DVT on terraces in the northern half of the Island; • 7 species characteristic of the evergreen closed forest that have significant populations elsewhere in the southeast Asia-Malesian-Pacific region -- the ferns Leptochilus decurrens, Pterodrys sympatica, Tectaria devexa var minor and Tectaria dissecta, the orchids Bryobium pubescens and Thrixspermum carinatifolium, and the shrub Amaracarpus pubescens; and, • 1 banyan species, Ficus saxophila, which occurs in semi-deciduous mesophyll vine forest on cliffs and limestone pinnacles and has significant distribution on terraces around the Island. It is also widely distributed from Indo-China to Papua New Guinea. The distribution of these species in the selected areas is summarised in Table 17, while Island wide data from Holmes and Holmes is provided in Table 15. Six of the above 12 taxa were recorded on Holmes and Holmes sites that fall within the selected areas (Table 16b). Two rare species that occur in disturbed habitats were observed on roadsides and abandoned mine areas near to, but not in, the selected areas. These were Leucas zeylandica (edge of regrowth on old stockpile near MCI 70/8) and Stronglydon lucidus (road verge south west of MCI 70/8; road verge north east of MCI 70/10). Holmes and Holmes also recorded both of these taxa within 100m of MCI 70/8 (Table 16b). In addition, Holmes and Holmes report one rare species, Abuliton listeri, which was not recorded in any of our surveys to occur at a site within 100m of MCI 70/12. Abuliton occurs on cliffs and scree slopes and is likely to have been a component of the DVT that lies just to the east of MCI 70/12. Page 14 of 76 July 2020 Christmas Island vegetation surveys Endemic species In addition to finding 5 endemic species considered in the potentially threatened categories above (Asplenium listeri, Colubrina pedunculata, Flickeringia nativitatis, Grewia insularis and Phreatia listeri), a further 5 Christmas Island endemics were recorded in the areas selected for possible future mining. These were: • the epiphytic orchid Brachypeza archytas that is characteristic of both the evergreen closed forests (map unit 10) and the semi-deciduous mesophyll vine forests (map unit 9) on the island’s plateau and terraces was found in areas MCI 70/8, 70/9, 70/10, 70/12, 70/14, 70/15 and 70/16); • the palm Arenga listeri, the vine Hoya aldrichii, and the tree/shrub Pandanus elatus that are very widespread and common components in both the evergreen closed forests (map unit 10) and semi-deciduous mesophyll vine forests (map unit 9) and were found in all 9 selected areas; and • the small tree Pandanus christmatensis that occurs as frequent elements in cliff flora, deciduous vine thickets (map unit 8) and ‘drier’ semi-deciduous mesophyll vine forests (map unit 9) and was found in these vegetation types in sites MCI 70/11 to 70/13. All 5 species have wide distributions on the Island (Du Puy 1993) and are well represented in vegetation types protected in Christmas Island National Park. Assessment of potential impacts of mining General overview Evergreen closed forest (map unit 10) is the vegetation type most likely to be affected by mining because it comprises approximately 80% of the vegetation that would be cleared in the areas selected for possible future mining and examined in this study. After exclusion of areas that could not be mined because of their lithology or topography, or need to be conserved for protection of threatened fauna and flora (e.g. all 113 ha of MCI 70/9) and to provide buffer zones for heritage areas and adjoining National Park boundaries, the maximum total area of this evergreen closed forest that could be cleared is 197 ha (Table 18). Slightly less than 13% of this forest (25.5 ha) had been subjected to significant previous anthropogenic disturbance (including old exploration drill-lines), with a further 8% affected by lower intensity disturbance, especially associated with understorey clearing. Clearing of the selected areas would therefore, at worst, result in the loss of around 5% of the Island’s remaining evergreen closed forest. Based on the quantitative data from plots established in this vegetation type, this would result in the destruction of an estimated 24,800 individual canopy and emergent trees with DBH greater than 50cm and require the felling of approximately 220,000 tonnes of vegetation biomass (note that these are crude estimates and in the case of aboveground biomass use Page 15 of 76 July 2020 Christmas Island vegetation surveys a simple but robust relationship based on basal area and heights of individual trees as applied by Proctor et al. 1983 in rainforest ecosystems in Sarawak). It would also result in the removal of three forest structural types (complex mesophyll vine forests with emergents, complex mesophyll vine forests and mesophyll vine forests) which have different potential habitat values based on their relative structural complexity and extent of vertical stratification. However, all of these three forest structural types are well represented in evergreen closed forests elsewhere on the plateau of the Island, especially in the National Park. Other native vegetation types likely to be cleared (Table 18) are semi-deciduous mesophyll vine forests (map unit 9) and secondary regrowth forests in previously cleared areas (map units 5 to 7). In both instances, these are very small areas compared to the total coverage of these vegetation types on the Island. With exclusions for protection of cultural sites and buffers, the total maximum area of semi-deciduous mesophyll vine forest that could be cleared under this proposal is 14.4 ha, which is less than 0.5% of the estimated extent of this, the Island’s most common vegetation type (mapped by Mitchell 1985 as “closed forest, shallow soil” and “closed forest, scree/pinnacle”). Of the up to 35 ha of the secondary regrowth forests proposed for clearing, 31 ha are advanced secondary forests on areas that have been cleared previously but not mined. Over time, if they are left undisturbed, these vegetation types are likely to develop into evergreen closed forests (see successional pathway 3 in Fig. 5 of Reddell et al. 2019). Despite the potential loss (in the short to medium term at least) of habitat, there are no individual native plant species in the selected areas for which mining would pose a significant conceivable threat to their continuing survival and viability. There are also no issues of fragmentation and isolation of critical plant populations. Clearing of the existing vegetation in small areas (1.7 ha) of MCI 70/10, 70/11, 70/13 that were covered by regrowth shrublands and Leucaena thickets (map units 1 to 3) would potentially have some benefits. These vegetation types, the result of previous high intensity disturbances, are dominated by naturalised and often aggressive weedy species. The destruction of this vegetation for mining would create the opportunity to successfully rehabilitate the areas in the future with a more appropriate native flora. While it was not possible to provide accurate estimates of the likely remaining overburden/soil that would be available for rehabilitation until the phosphate resource (and its grades) in the selected areas had been determined, we have attempted to make some crude preliminary estimates of the likely volume of these materials. The purpose of these calculations (based on information provided by PRL) is to ensure that there would be adequate remaining overburden/soil to provide a minimum 0.3m cover over at least 5% of the mined area. The crude estimates of overburden remaining in selected area for use in rehabilitation are summarised in Table 19 and are based on: 1. the area to be mined after all non-mineable areas (e.g steep terrain and unsuitable lithology in MCI 70/11 and 70/12) and MCI 70/9 are excluded, but not accounting for 17 to 20 ha of Page 16 of 76 July 2020 Christmas Island vegetation surveys exclusion areas and buffers that could be associated with conservation, heritage and aesthetic features; 2. the estimated volume of resource in the mining areas from historical (and often widely spaced) drilling data, or inferred from the nature of the resource in adjacent existing leases; and, 3. the estimated proportion of soil that would not be utilised as a phosphate resource, based on the experience of mining personnel and the likely grade of phosphate in the selected areas. Until the precise shape, size and orientation of clearings in the selected areas can be determined by pre-mine drilling programs, it is difficult to predict location-specific edge effects. However, buffering all National Park and all other boundaries with primary forest by a 60m wide uncleared area would be minimise edge effects on adjoining forest areas. Potential impacts on vegetation type The data in Table 18, which reports the total areal extent of each of the mapped vegetation types in the selected areas, are based on the assumption that a successful rehabilitation strategy could be implemented. The major implications for the long-term vegetation cover in these areas are that: 1. there would be a significant net loss of evergreen closed forests (around 197 ha) and a commensurate increase in semi-deciduous mesophyll vine forests and deciduous vine thickets (semi-deciduous mesophyll vine forest and DVT); 2. approximately 30ha of advanced secondary forests (map units 6 and 7) that have regenerated naturally after previous disturbance (they were cleared but not mined), and which over time have the potential to develop into evergreen closed forest, would be removed and converted to semi-deciduous mesophyll vine forest and DVT; and, 3. current exotic shrublands (2.2 ha) would be eliminated and replaced by native vegetation types. This long term change in vegetation types has important implications in setting appropriate monitoring criteria and standards, together with ‘benchmarking’ sites for rehabilitation (Reddell et al. 2019). Impacts on EPBC-listed and other significant flora As outlined above, the vegetation type likely to be most impacted by possible future mining in these selected areas was evergreen closed forest. On an Island-wide basis, this forest type provides habitat for 19 of the 54 species of plants of recognised conservation significance (Table 20), including 15 taxa that are primarily restricted to it. Nine of these 19 species were found in the vegetation surveys of the selected areas (Table 20), with 7 being largely restricted to evergreen closed forest (Amaracarpus pubsecens, Bryobium pubescens, Leptochilus decurrens, Phreatia listeri, Pteridrys Page 17 of 76 July 2020 Christmas Island vegetation surveys syrmatica, Tectaria devexa var minor and Tectaria dissecta). Other vegetation types, especially more seasonal vegetation types on shallow soil profiles that were likely to be much less impacted by possible future mining, include most of the Island’s plants of highest conservation significance (35 of 55 species), including 8 of the 10 most threatened species on the Island. In framing our assessment of the possible impacts of mining on individual plant species of conservation significance we have been cognisant of the following. • The thorough assessment of the conservation status of Christmas Island flora that was completed by Holmes and Holmes (2002). This key source document and dataset provided a comprehensive list of potentially rare and threatened species, based on ROTAP guidelines (Briggs and Leigh1995), together with very significant amounts of information on the distribution of these species across the Island from previous work and from their own detailed collections on 405 sites. However, we also recognise that despite it being comprehensive, this work is still only a sampling of the Island’s flora and that other locations and populations of many of the significant flora are almost certain to be found into the future. • Mining the selected areas would focus on the evergreen closed forest and it is this habitat (and the species dependent upon it) that would be most impacted with the potential clearing of up to 6% of the remaining area of this vegetation on the Island. • Whether there is any evidence that (a) any species are particularly concentrated in the selected areas (compared with other areas of closed forest on the Island) or the that they contain significant disjunct populations, or (b) clearing and mining of these areas would isolate and fragment any significant populations of these species in the surrounding areas. Species listed under the EPBC Act Asplenium listeri A single population of A. listeri was found just to the east of MCI 70/12. This endangered endemic has specific requirements for partially-sheltered habitat on limestone cliffs and outcrops. These areas would not be cleared or directly impacted by mining. The only conceivable threats to this species from mining are likely to be indirect, through possible modifications to the density of surrounding tree canopies which could then affect local micro-climate and the susceptibility of these sites to shrub encroachment and consequently more intense shading. To protect this population of A. listeri from any of these possible indirect effects of mining in MCI 70/12, the structural integrity of the canopy of the DVT that is immediately adjacent to and provides some shelter for the A. listeri could be maintained. A minimum 50m wide conservation buffer on the western side of this population of A. listeri could provide this protection. Tectaria devexa var minor Tectaria devexa var minor was present in low numbers in the evergreen closed forest habitat in Page 18 of 76 July 2020 Christmas Island vegetation surveys MCI 70/8. We detected one individual in the 13.5 ha of this habitat type that we surveyed intensively. The surveyed area represented approximately 13% of the potential habitat (evergreen closed forest) for this species in that location. Holmes and Holmes found 6 individuals of T. devexa at a site near the southern boundary of this area. Although very difficult to estimate definitively, we suggest the maximum number of individuals of this species present in MCI 70/8 could be between 1 and 40. We did not find this species in any of the other areas selected for possible future mining, despite intensively surveying more than 34 ha of potential habitat in MCI 70/9, 70/10, 70/14, 70/15 and 70/16. Similarly, Holmes and Holmes found no other populations of this species at their sites that were on or near to the selected areas. Indeed, they only recorded three other populations of T. devexa in the east of the Island (Table 16) and these comprise less than 2% of the more than 400 individuals of T. devexa that they found on the Island. In their appraisal of the conservation status of T. devexa on Christmas Island, Holmes and Holmes suggested that (based on ROTAP guidelines; Briggs and Leigh1995) this taxa should be considered rare rather than endangered. They recognised no current conceivable threats to its conservation. In assessing the impacts of possible future mining on T. devexa in MCI 70/8, we considered three levels of possible mitigating action: 1. identify all individual plants and establish conservation buffer zones to protect them from mining operations; 2. identify individual plants prior to the commencement of clearing operations and translocate them to suitable habitat nearby; and, 3. no specific mitigation, with clearing operations destroying any individual T. devexa within areas that would be mined. On balance we suggest that the destruction of the habitat of Tectaria devexa var minor in MCI 70/8 would have no significant impact on the long-term viability of this species on Christmas Island. Based on Holmes and Holmes data, more than 97% of the currently known individuals are protected in the western and central areas of the Island within the National Park. However, because of its small size and likely ease of transplanting, intensive searches could be made (as part of any pre-mining site survey of this area) to locate as many individual of T. devexa as possible, excavate them and transplant them to suitable habitat in other nearby areas in the east of the Island. Carmona retusa Carmona is present, and often locally common, in the areas selected for possible future mining in the northeast of the Island where densities of 10’s to 1,000’s of stems per ha occur. Its primary habitat is as an understorey shrub in drier semi-deciduous mesophyll vine forest and in DVT. Much of this primary habitat in these areas would be either excluded from mining (e.g. the DVT in 70/11) or would be marginal for mining (e.g. MCI 70/13) because of the shallow soil profiles. Of more interest Page 19 of 76 July 2020 Christmas Island vegetation surveys was some of the secondary habitat of Carmona (where it generally occurred at much lower densities) in previously disturbed sites either on areas that had been cleared but not mined, or on old mine stockpiles (e.g. along the western edge of MCI 70/12). However, irrespective of which areas of Carmona habitat were to be mined, they are small and insignificant compared to the total habitat of this species which is widespread and very common on all terraces of the Island, especially in the north and northeast (see Du Puy 1993). Because of its obvious abundance on the Island, Holmes and Holmes did not consider it to fall into any of the threatened categories under ROTAP (Briggs and Leigh 1995) guidelines. As a consequence of its abundance and distribution on the Island, we did not recognise a significant impact or threat to the viability of this species from mining that might occur in the areas selected in this study. Consequently, no measures are suggested to mitigate impacts of the likely destruction of individual Carmona plants. In the long term, the impact of the mining on Carmona would probably be positive as its preferred habitat (drier semi-deciduous mesophyll vine forest and DVT) would increase in area as a result of rehabilitation and Carmona itself would be a component species used in the rehabilitation program for these sites. Pneumatopteris truncata This species has a specialised habitat associated with groundwater seepages and permanently moist areas on the terraces and occurs at sites that are remote from, and would be unaffected by, the possible future mining operations in the areas selected in this study. Consequently, no specific impact mitigation measures are proposed for this taxon. Other plant species proposed endangered or vulnerable No plant species suggested for future EPBC-listing as endangered or vulnerable by Holmes and Holmes (2002) were found in the areas selected for possible future mining. We are confident this does not reflect any inadequacies in the survey design, but merely that there was very little or no potential habitat for these species in areas with economic phosphate deposits. Two vulnerable taxa, Spondias cytherea and Cycas rumphii, were found close to the boundary of MCI 70/11 but, because of the unfavourable lithology on the eastern side of this site, none of the area in the immediate vicinity would be mined or disturbed by mining operations. Consequently, we conclude that there would be no impacts on populations of any of the proposed endangered or vulnerable taxa on the Island. Species proposed as poorly-known or rare One species proposed as ‘poorly-known but potentially threatened’ and 12 species proposed as ‘rare’ by Holmes and Holmes (2002) were found in the areas selected for possible future mining. A ‘poorly-known’ species, Blumea balsamifera, was found in a disturbed area with Macaranga regrowth in MCI 70/9 but this area was deselected by PRL because it provided nesting habitat for the Page 20 of 76 July 2020 Christmas Island vegetation surveys endangered Abbott’s Booby. This species was not recorded by Holmes and Holmes in their survey but was previously reported from regrowth around roadsides at the Central workshops and North West Point (Du Puy 1993). Four other poorly-known species dependent on evergreen closed forest (Table 20) were not found in our survey or in the island-wide survey by Holmes and Holmes. Two of these were known only from the original collections made around 100 years ago and are possibly extinct. The remaining two were known only from collections from the west and/or central areas of the Island (Du Puy 1993) that are remote from the areas selected for possible future mining. Twelve species suggested as rare by Holmes and Holmes (2002) were found in the selected areas. Three of these (Colubrina pedunculata, Ficus saxophila and Grewia insularis) are characteristic of dry semi-deciduous mesophyll vine forest and DVT forest types on shallow soils or limestone outcrops and, except for up to 6.2ha of MCI 70/13, occurred on areas that would not be affected. Even if mining was to occur in some or all of the semi-deciduous mesophyll vine forest vegetation in MCI 70/13, only a very small proportion of the Island-wide population of these taxa would be destroyed and there is no conceivable threat to their long-term survival or viability. The remaining 9 rare plant species encountered in the survey occurred principally in evergreen closed forest (Table 20). These species comprise 4 epiphytic orchids (Bryobium pubescens, Flickeringia nativitatis, Phreatia listeri and Thrixspermum carinatifolium), 4 ground ferns (Leptochilus decurrens, Pteridrys sympatica, Tectaria devexa var minor and Tectaria dissecta) and the shrub (Amaracarpus pubescens). Tectaria devexa has already been considered under its current EPBC-listing above. Of the rest, two orchids (Flickeringia nativitatis and Phreatia listeri) are endemic to Christmas Island, with the other taxa all having significant distributions in the southeast Asia-Malesian-Pacific region. The two endemic orchids (Flickeringia nativitatis and Phreatia listeri) were both found to be numerous in 7 of the selected areas (Table 17). Both are widespread across the Island (Du Puy 1993), with Holmes and Holmes reporting Flickeringia at 99 sites (comprising more than 47,000 individuals) and Phreatia at 36 sites (~3,200 individuals). In our assessment, there would be no significant impact of mining in the selected areas on the viability of these species. Of the remaining 6 taxa that are dependent on evergreen closed forest, 4 (Bryobium pubescens, Pteridrys sympatica, Tectaria dissecta and Thrixspermum carinatifolium) have wide distributions across the Island (Du Puy 1993; Holmes and Holmes 2002; Table 15) with no significant concentrations of populations in, or near, the selected areas. In all four instances, while clearing of these areas for mining without any mitigation would destroy individual plants and populations of these taxa, our assessment is that there would be no significant impact on their long-term survival and viability on the Island. The final two rare species that are dependent on evergreen closed forest (Amaracarpus pubescens and Leptochilus decurrens) are widespread overseas but have localised or restricted distributions on Page 21 of 76 July 2020 Christmas Island vegetation surveys the Island. Amaracarpus is reported from the west, centre and southeast of the Island. We found 2 populations comprising 6 individuals in MCI 70/9 and a single individual in MCI 70/15. Holmes and Holmes recorded 20 individuals at two localities, one site in MCI 70/15 and the other in the west of the Island near Murray Hill. Holmes and Holmes suggest that there were no conceivable threats to this species, but also noted that numbers seemed to have declined since it was first collected more than 100 years ago. Future mining would have no impact on the population of Amaracarpus in MCI 70/9 as this area is to be protected as Abbott’s Booby habitat. The impact of future mining in MCI 70/15 is less clear as so few population records of this species are available (despite its distribution in evergreen closed forests across the south, central and west of the Island). On balance, we suggest that there is likely to be no significant impact. However, if mitigation was necessary, we suggest that a conservation buffer could be established surrounding the population in MCI 70/15 (which occurs in the central-western section of this area). We found the ground fern Leptochilus decurrens that occurs from India to SW China and through Malesia to Sulawesi on 3 of the selected areas (Table 17) with a total of 10 individuals being observed. On Christmas Island this species is restricted to evergreen closed forests in scattered but localised populations across the plateau of the Island at Murray Hill, Aldrich Hill, near South Point (in MCI 70/8) and Phosphate Hill. Our records in MCI 70/9 and MCI 70/14 add new locations to its previously known distribution. Holmes and Holmes recorded it at 3 sites in the west and centre of the Island, and 4 sites in the southeast, all of which were in the southern part of MCI 70/8. Of the approximately 250 plants they found, 60% were in sites within this southern area of MCI 70/8. Our records together with those of Holmes and Holmes suggest that this species is far more widespread on the Island than previously reported. Holmes and Holmes (2002) identified no conceivable current threats to this species. In our view, this is the most difficult species of the significant flora on which to make an impact assessment. While the species is clearly distributed across the plateau of the Island and most of the known locations are protected in the National Park, the high population density at sites in the southern part of MCI 70/8 is potentially of local significance. In our view, further information and observations on the populations of this species on the Island are required to make a definitive assessment of the possible impact of future mining in the southern section of MCI 70/8 on this species. If this population is recognised as significant, two impact mitigation measures appear to be feasible. These are (1) identification of the core population of this species in the southern section of MCI 70/8 and establishment of a local conservation buffer zone around this area, or (2) propagation of individuals from this population and their establishment in appropriate habitat in nearby areas of evergreen closed forest followed by mining of the original habitat. Five other rare species that are known to occur in the Island’s evergreen closed forest (Table 20) were not encountered in the areas selected for possible future mining during our surveys. However, one of these taxa (the vine Stronglydon lucidus) did occur at 2 locations on disturbed forest edges near these areas. The remaining four species are known either entirely or largely from the west and central Page 22 of 76 July 2020 Christmas Island vegetation surveys areas of the Island (Du Puy 1993; Holmes and Holmes 2002). Endemic species Five endemic species (Arenga listeri, Brachypeza archytas, Hoya aldrichii, Pandanus christmatensis and Pandanus elatus) that are not categorised or proposed as threatened were recorded in the areas selected for possible future mining. All have wide distributions across the Island with the vast majority of their populations in areas outside the selected areas, including being well represented in the National Park. Mining in the selected areas would have no significant impact on these taxa. Summary As described by Reddell et al. (2019), the flora of Christmas Island comprises more than 400 species of vascular plants of which over half are indigenous to the island and just less than half have naturalised since human occupation. The general taxonomic status and affinities of the flora are relatively well known but detailed records of population distributions are limited for many species. New species of ferns, herbs and shrubs continue to be added to the flora as a result of further collections. The indigenous flora has very strong taxonomic relationships with those of the Indo-Malayan and Malesian regions and many species are shared with these regions. Despite its isolated location, estimated 10-million year history above sea level, and diverse ‘high-island’ landscape, only 18 species are known to be endemic. At the time of our field studies, four species, the endemic lithophytic fern Asplenium listeri, the ground ferns Tectaria devexa var minor and Pneumatopteris truncata, and the shrub Carmona retusa were listed as endangered or vulnerable under the Australian Government’s EPBC Act (1999). It should be noted however, that strict application of the Rare or Threatened Australian Plant (ROTAP) guidelines (Briggs and Leigh 1995) may not adequately reflect the actual conservation status of the flora of Christmas Island. Under the guidelines, the conservation status of the Island’s biota is assessed solely on species occurrence in areas under Australian sovereignty although the Island is biogeographically part of Malesia. As a consequence, species that are either widespread and/or locally abundant in their native habitat on Christmas Island can be classified as rare under these guidelines purely because these habitat areas are restricted in area and these taxa are absent from mainland Australia. There are widespread and common Asian and IndoPacific species with small outlier populations on Christmas Island that fall into this category and are potentially afforded the same conservation status as Christmas Island endemics with similarly small total population sizes on the Island. Comprehensive surveys and mapping of the vegetation on a number of areas selected for possible future mining on Christmas Island, in concert with an evaluation of its ecology, enabled an assessment of the potential impacts of disturbance by the possible future mining of phosphate in a Page 23 of 76 July 2020 Christmas Island vegetation surveys number of areas selected on the basis of significant phosphate reserves. The research targeted the possible impacts of mining on forest types as well as on the occurrence and distribution of EPBClisted and other significant flora. This was based on the fact that mining would clear the vegetation cover and substantially remove the phosphate ore, which is the substrate in which the vegetation had established and grown. Comments on the significance of the impact (in terms of whether there could be a detriment to species distribution, forest type and habitat on the Island as a whole) and suggestions for interventions that could mitigate any impact (such as establishment of buffer zones to minimize disturbance, or transplantation of threatened individual plants) were made after analysis of the survey data. In fact, mining has not proceeded. As well as generating new information on the ecology and distribution of a number of plants, the survey data also contributed to the development of a self-sustaining rehabilitation strategy for mined areas (Reddell et al. 2019), given that mining forever removes the phosphate-rich regolith and changes the local landscape, including the hydrology (Puhalovich 2005). Analysis of the floristics, ecology and structure of the vegetation, together with observations on secondary and natural successional pathways following mining and other disturbances, and the characteristics of natural vegetation on parts of the Island that can be regarded as analogues of mined areas, are key. Acknowledgements This research was undertaken while the authors were working at Earth-Water-Life Sciences P/L, Darwin. Phosphate Resources Ltd (PRL) funded the project as a component of a Draft Environmental Impact Assessment prepared submitted in 2005 and provided important logistical support for the work. We thank Mark Bennett, Jude de Cruz and the staff of the Environment Section of PRL for their support in the design and implementation of the field work. Jeff Clausen from Parks Australia North shared his knowledge on the flora of the Island. Philippe Puig (EWL Sciences) produced the maps and analysed spatial data for the report. The Department of Environment and Heritage provided access to confidential location and population data from the Holmes and Holmes (2002) report on species of conservation significance on Christmas Island. References Barker RM, Telford IRH (1993) Boraginaceae. In ‘Flora of Australia Volume 50, Oceanic Islands 2’. Australian Biological Resources Survey pp. 353-360. Briggs J, Leigh J (1995) Rare and threatened Australian plants. (CSIRO Publishing: Collingwood, Victoria). Du Puy DJ (1993a) Christmas Island. In ‘Flora of Australia Volume 50, Oceanic Islands 2’. Australian Biological Resources Survey, pp. 1-30. Page 24 of 76 July 2020 Christmas Island vegetation surveys Environment Protection Biodiversity Conservation Act (EPBC Act) (1999). Australian Government. Holmes J. Holmes G (2002) Conservation status of the flora of Christmas Island, Indian Ocean. Report to Environment Australia/Parks Australia North. (Glenn Holmes and Associates, September 2002). Mitchell BA (1985) A vegetational survey of Christmas Island, Indian Ocean. Unpublished report to Australian National Parks and Wildlife Service. 40pp. Proctor J, Anderson JM, Chai P, Vallack HW (1983) Ecological studies in four contrasting lowland rain forests in Gunung Mulu National Park, Sarawak. Journal of Ecology 71, 237-260. Puhalovich AA (2005) Measured and model predicted water movement in the unsaturated zone, Christmas Island, Indian Ocean. In Proc. of IAH-NZHS-NZSSS Joint Intnl. Conf. (‘Where Waters Meet’), Auckland, New Zealand, 28 Nov to 2 Dec 2005. Reddell P, Zimmermann A, Milnes AR (2019) Floral Ecology of Christmas Island, Indian Ocean: key to self-sustaining phosphate mine rehabilitation. (Unpublished report, ResearchGate) Page 25 of 76 July 2020 Christmas Island vegetation surveys Table 1. Proportions of the nine areas selected for possible future mining covered by strategic vegetation transects Site ID MCI MCI MCI MCI MCI MCI MCI MCI MCI 70/ 8 70/ 9 70/ 10 70/ 11 70/ 12 70/ 13 70/ 14 70/ 15 70/ 16 TOTAL Total area ( ha) Total mineable area ( ha) Area covered by strategic transects ( ha) % of area covered by strategic transects 106.9 113.1 64.1 13.0 18.4 7.4 52.2 13.9 5.7 106.9 113.1 64.1 9.8 10.1 7.4 52.2 13.9 5.7 8.6 4.8 5.5 1.6 1.9 0.9 5.8 1.7 0.6 8.0 4.2 8.6 16.3 18.8 12.2 11.1 12.2 10.5 394.6 383.2 31.4 8.2 Page 26 of 76 July 2020 Christmas Island vegetation surveys Table 2. Conservation status, distribution and habitat on Christmas I sland of plant species that ( a) were EPBC- listed plant species or (b) recommended for EPBC-listing by a recent consultant report (Holmes & Holmes 2002) Species Conservation status Distribution Habit Habitat on Christmas I sland listeri EPBC -- endangered H&H -- endangered Endemic to CI Lithophytic fern Pneumatopteris truncata EPBC – endangered H&H – endangered SE Asia & Malesia Ground fern Seepages & permanently moist sites Tectaria devexa var minor EPBC -- endangered H&H -- rare Species from SE Asia to Queensland, var minor CI & Sri Lanka only Ground fern Evergreen closed forest, under canopy & in canopy gaps; principally in west of I sland EPBC -- vulnerable H&H -- not listed S Asia, Malesia to Pacific Shrub SDMVF & DVT, secondary forests in disturbed areas ( a) EPBC-listed taxa Asplenium Carmona retusa Limestone outcrops & cliffs ( b) Taxa recommended for EPBC-listing as Endangered or Vulnerable (Holmes & Holmes 2002) Asystasia alba H&H -- endangered Endemic to CI Herb Clearings & margins of SDMVF & DVT on lower terraces; W & NE of island Dicliptera maclearii H&H -- endangered Endemic to CI Herb Margins & gaps in SDMVF & other vegetation on lower terraces; NW & NE of island Blumea lanceolaria H&H -- endangered S Asia & Malesia Herb Open sites in CMVF, SDMVF (e.g. tree fall gaps, clearings & drilllines); W of island Muellerargia timorensis H&H -- endangered Malesia & NE Australia Vine Margins of SDMVF & DVF, lower terraces; NW of island only Cycas rumphii H&H -- vulnerable Malesia to Pacific I slands Cycad Open areas in SDMVF to DVT on clifftops & limestone scree; estimated population around 100 plants Spondias cytherea H&H -- vulnerable SE Asia plus widely cultivated Tree Dendrocnide peltata var. murrayana H&H -- vulnerable Species common in Malesia; var murrayana endemic to CI Small tree SDMVF Openings, edges and large gaps in SDMVF; NE & NW of island Page 27 of 76 July 2020 Christmas Island vegetation surveys Table 3. Possible areas of habitat in areas selected for possible future mining for (a) existing and (b) recommended EPBC-listed plant species, and implications for the sampling and assessment strategy. Underlining indicates endemic taxa. Status Possible habitat in areas selected for future mining Asplenium listeri EPBC -- endangered (H&H -- endangered) Cliffs & semi-exposed limestone outcrops on fringes of MCI 's 70/ 8, 10 & 12 The habitat for this species is unsuitable for mining and will not be cleared. However, because of its specific requirements for partial shelter, impacts need to be assessed in relation to possible mining where evergreen closed forest is close to cliff areas in MCI 's 70/ 8 and 70/ 12 that are potential habitat. Pneumatopteris truncata Endangered Nil This species occurs in seepage areas and other permanently moist sites, usually in mid or lower terrace areas. There is no suitable habitat of this type that is either within the selected areas or in downstream areas that could potentially be impacted by the proposed activities. Species I mplications for sampling & assessment strategy ( a) EPBC-listed taxa Tectaria devexa var minor EPBC -- endangered (H&H -- rare) Under canopy of CMVF & MVF in MCI 's 70/ 8, 70/ 9, 70/ 10 & 70/ 14 Potential habitat for this species occurs over many of the likely phosphate deposits in the selected areas. However, there are very few previous records of this species from these areas. The majority of the population is known to occur in the west of the I sland in areas of closed evergreen forest that are unaffected by this mining proposal. Carmona retusa EPBC -- vulnerable (H&H -- not listed) Under canopy of SDMVF & DVT in MCI 's 70/ 11, 12, 13 & 15; also in secondary forests in MCI 's 70/ 10, 11, 12 & 13 There is potential habitat for this species in natural vegetation (over marginal or uneconomic phosphate deposits) and in secondary forest in the selected areas, largely in the north-east of the I sland (Figures 9 & 10). However, these areas represent a very small percentage of the total habitat for this common species on the I sland. ( b) Taxa recommended for EPBC listing as Endangered or Vulnerable (Holmes & Holmes 2002) Asystasia alba Endangered ?? Margins of SDMVF & DVT's in MCI 's 70/ 11 & 13 (usually on lower terraces) There is very little potential habitat for this species on the selected areas. Where this potential habitat does occur in the north-east of the I sland it will not be mined because of the shallow soil and consequently limited or non-existent phosphate resources. Dicliptera maclearii Endangered ?? Margins of SDMVF & DVT's in MCI 's 70/ 11 & 13 There is very little potential habitat for this species on the selected areas. Where this potential habitat does occur in the north-east of the I sland it will not be mined because of the shallow soil and consequently limited or non-existent phosphate resources. Muellerargia timorensis Endangered ?? Margins of SDMVF & DVT's in MCI 's 70/ 11 & 13 (only recorded on NW of the I sland to date) There is very little potential habitat for this species on the selected areas Where this potential habitat does occur in the north-east of the I sland it will not be mined because of the shallow soil and consequently limited or non-existent phosphate resources. Blumea lanceolaria Endangered ?? Clearings, treefall gaps & drill-lines in CMVF & MVF in MCI 's 70/ 8, 9, 10, 12, 14 & 15 There are no records of this species from the eastern side of the I sland despite significant areas of potential habitat existing on the edges of clearings and in evergreen closed forest disturbed by drill-lines. Cycas rumphii Vulnerable Exposed & open areas in SDMVF to DVT on clifftops & limestone scree on margins of MCI 's 70/ 8, 11, 13 & 15 There is very little potential habitat for this species on the selected areas. Where this potential habitat does occur it will not be mined because of the shallow soil and consequently limited or non-existent phosphate resources. Spondias cytherea Vulnerable SDMVF & regrowth on southern edge of MCI 70/ 11 Although not recorded previously on the selected areas, potential habitat for this species does occur in SDMVF and in secondary forest on the southern edge of MLA 70/ 12, an area in close proximity to an existing population. Page 28 of 76 July 2020 Dendrocnide peltata var. murrayana Christmas Island vegetation surveys Vulnerable Cliff tops & exposed or open margins of SDMVF & DVT in MCI 's 70/ 10, 70/ 11, 70/ 12 & 70/ 13 There is very little potential habitat for this species on the selected areas. Where this potential habitat does occur it will not be mined because of the shallow soil and consequently limited or non-existent phosphate resources. Page 29 of 76 July 2020 Christmas Island vegetation surveys Table 4. Summary ( a) distribution, ( b) habitat on Christmas I sland and ( c) likely occurrence in the areas selected for possible future mining, of plant species considered to be ‘Rare’ or ‘Poorly–known’ in Holmes & Holmes (2002). Species Distribution Habit Occurrence on Christmas I sland Selected areas w ith potential habitat Comments on likely occurrence in the selected areas 1. Primarily in evergreen closed forests ( CMVF & MVF) Amaracarpus pubescens SE Asia to Malesia Shrub Plateau MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Bryobium pubescens I ndonesia Orchid Plateau & upper terraces, abundant MCI 70/ 8, 9, 10, 12, 14, 15 & 16 * Didymoplexis pallens South Asia to Polynesia SE Asia, N Aust to Polynesia ? Plateau, only known from near Murray Hill Plateau, western & central areas only (?) MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Plateau MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Plateau, northern half MCI 70/ 8, 9, 10, 12, 14, 15 & 16 ? Plateau (only known from collection in 1898) MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Possibly extinct Plateau & upper terraces, abundant MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Common across the range of these forest types Fern Plateau & upper terraces, widespread MCI 70/ 8, 9, 10, 12, 14, 15 & 16 No records in SE plateau area (i.e. MCI 's 70/ 8, 14, 15 & 16) Orchid Plateau, western & central parts of the I sland MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Only record from eastern side of the I sland is between MCI 's 70/ 8 & 14 Huperzia phlegmaria Terrestrial orchid Fern ally Fern MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Leptochilus decurrens SE Asia to Sulawesi * Peperomia laevifolia Malesia * Peperomia rossi Endemic to CI Phreatia listeri Endemic to CI Pteridrys syrmatica SE Asia to PNG Taeniophyllum hasseltii Malesia Tectaria devexa var minor Sri Lanka Fern Plateau, primarily western & central areas but also in SE MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Tectaria dissecta SE Asia to SW Pacific Fern Plateau & upper terraces, common but not in NE MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Thelasis capitata Malesia Areas of the plateau above approx 250m MCI 70/ 8, 9, 10, 12, 14 & 16 * Zeuxine exilis Endemic to CI Epiphytic herb Epiphytic herb Orchid Orchid Terrestrial orchid ? Plateau, near Murray Hill (only known from original collection,1904) Common across the range of these forest types No records on the eastern side of the I sland Only records of eastern side of the I sland are close to MCI 70/ 10 Possibly extinct 2. More w idespread from CMVF to SDMVF Balanophora abbreviata Africa to Polynesia Parasite Flickingeria nativitatis Endemic to CI (+ Java ??) I ndian Ocean to Pacific incl N Aust Orchid Strongylodon lucidus Thrixspermum carinatifolia Malesia Climber Orchid Mainly western plateau MCI 70/ 8, 9, 10, 12, 14, 15 & 16 More common in SDMVF Plateau & terraces, widespread & abundant Plateau, widespread MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Common across the range of these forest types MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Prefers more open sites, plus fringes of minefields MCI 70/ 8, 9, 10, 12, 14, 15 & 16 Only records of eastern side of the I sland are close to MCI 70/ 9 Plateau & upper terraces in western & central parts of the I sland, abundant Page 30 of 76 July 2020 Christmas Island vegetation surveys 3. SDMVF & DVT Colubrina pedunculata Endemic to CI Tree NE & W of I sland, common to locally abundant MCI 70/ 13 , also in MCI 70/ 11 but in areas that will not be mined Shallow soils near limestone outcrops, areas have no significant phosphate deposits for mining Ficus saxifolia SE Asia & Malesia Tree Terraces & cliffs, common MCI 70/ 13 , also in MCI 70/ 11 but in areas that will not be mined Restricted to limestone outcrops, cliffs, scree or very shallow soil, areas that will not be mined Grewia insularis Endemic to CI Shrub NE & NW of I sland I lligera elegans Endemic to CI Shrub Terraces in NE & west of I sland Characteristic of shallow soils on northern terraces Typically in more open areas in these vegetation types Remusatia vivipara Africa-Malesia-N Aust MCI 70/ 13 , also in areas that will MCI 70/ 13 , also in areas that will MCI 70/ 13 , also in areas that will Epiphytelithophyte Single record from Phosphate Hill in 1897 in MCI not be in MCI not be in MCI not be 70/ 11 but mined 70/ 11 but mined 70/ 11 but mined 4. Disturbed areas ( clearings & forest margins) Abelmoschus manihot Malesia Shrub Central plateau * Blumea balsamifera * Cinnamomum iners South Asia- Malesia Shrub Plateau, road verges & minefield edges I ndia to Philippines Climber East coast only, near Ross Hill Gardens Cleome gynandra Worldwide tropics * Jacquemontia paniculata Africa to Malesia Twiner Leucas zeylandica S Asia to Malesia Herb Herb Lycianthes biflora S Asia to Malesia Herb Momordica charantia Africa-Asia-N Aust Climber Climber ?? NE & NW, mainly coastal Eastern areas of I sland NE & central areas Central plateau & settlement Mucuna pruriens Africa-Asia- Malesia Spermacoce mauritiana Pan-tropical Herb Western side of I sland * Tectaria sp. Malesia Fern Triumfetta suffruticosa Malesia to Polynesia Terraces & plateau; disturbed areas + exposed limestone outcrops NE & east of I sland Vitis flexuosa Japan to SE Asia Climber Northern half of I sland * Zehneria alba Endemic to CI Climber NE only Shrub Settlement Forest edges & small areas of secondary forest & clearings in MCI 70/ 8, 70/ 9, 70/ 12, 70/ 13, 70/ 14, 70/ 15 & 70/ 16; larger areas of edges & secondary regrowth in 70/ 10 & 70/ 11 Preferred habitat is peripheral to m ost of that in the selected areas. Mining will potentially create more short-term habitat for these species 5. Shoreline, coastal cliffs & ledges, scree slopes Abutilon listeri Endemic to CI Shrub Coast & coastal cliffs, common Nil Commicarpus chinensis Africa to Malesia Shrub NW Point I schaemum nativitatis Endemic to CI Grass Northern & western coastline Nil Nil * Selaginella alutacia Malaysia- I ndonesia Smith Point (single record from 1904) Nil * Setaria clivalis Malesia Grass ? Coastal shrubland, single record 1904 Nil Triphasia trifolia SE Asia to Malesia Shrub Flying Fish Cove Nil SE Asia to Pacific Mangrove Localised occurrence below Ross Hill Nil Lithophyte 6. Other Cynometra ramiflora Page 31 of 76 July 2020 Christmas Island vegetation surveys Table 5. Total areas surveyed for threatened species ( a) in each site selected for possible future mining and (b) by vegetation types. This includes all areas covered by the strategic transects, intensive measurement plots and focussed survey blocks. ( a) Area surveyed for threatened species by lease Total area ( ha) Total mineable area ( ha) 106.9 113.1 64.1 13.0 18.4 7.4 52.2 13.9 5.7 TOTAL * TOTAL minus 70/ 9 Site ID MCI MCI MCI MCI MCI MCI MCI MCI MCI 70/ 8 70/ 9 70/ 10 70/ 11 70/ 12 70/ 13 70/ 14 70/ 15 70/ 16 Total area w ithin selected site surveyed for threatened species Area adjacent to selected site surveyed for threatened species ( ha) (in ha) (as % of total mineable area) 106.9 113.1 64.1 9.8 10.1 7.4 52.2 13.9 5.7 13.6 7.6 9.0 3.8 4.1 2.4 10.6 3.1 0.6 12.7 6.7 14.0 38.8 40.6 32.4 20.3 22.3 10.5 2.3 0.8 0.1 0.9 1.5 0 1.9 0.8 0 394.6 383.2 54.8 14.3 8.3 281.5 270.1 47.2 17.5 7.5 * this total accounts for the exclusion of lease MCI 70/ 9 which was removed from the proposal to protect nesting habitat for Abbott’s Booby ( b) Area surveyed for threatened species by each major vegetation type Vegetation typeA Total mineable area of each vegetation type in the selected areas ( ha) Total area of vegetation type surveyed w ithin the selected areas ( ha) % of vegetation type surveyed in the selected areas Mixed shrublands Muntingia shrublands Leucaena thicket Shrubland-secondary forest mosaic Macaranga secondary forest to 12m Advanced Macaranga secondary forest Advanced mixed secondary forest Deciduous vine thicket Semi-deciduous mesophyll vine forest Evergreen closed forest 0.6 0.6 1.0 5.6 0.4 16.3 28.2 0.2 17.8 302.5 0.06 0.02 0.39 0.7 0.04 1.35 2.64 B 0.2 3.7 47.5B 10 3.3 39 12.5 10 8.3 9.3 100 20.8 15.1 AFor a description of each of the vegetation mapping units refer to Table 11. BIncludes a total of 7.6 ha of surveyed area within lease MCI 70/9 (which was removed from the proposal to protect nesting habitat for Abbott’s Booby). Page 32 of 76 July 2020 Christmas Island vegetation surveys Table 6. Vegetation mapping units for areas selected for possible future mining on Christmas I sland. Unit no. Vegetation type Description and comments 1 Mixed shrublands Closed to sparse vegetation 0.5 to 2m in height with occasional emergents to 4m. Dominated by exotic weedy species including Cordia curassavica, Turnera ulmifolia, Tecoma stans, Leucaena leucocephala, Mimosa pudica, Starchytarpheta jamaicensis, Sida acuta and a number of herbaceous Euphorbiaceae and Asteraceae. A grass and sedge component is present in the ground layer and can dominate in some of the more open areas. These areas are the result of repeated, high intensity disturbance. 2 Muntingia shrublands Mid-dense to sparse thickets to 4m dominated by the exotic shrub Muntingia calabura. abandoned minefields away from forest boundaries. 3 Leucaena thickets Closed, dense thickets to 6m in height, the exotic Leucaena leucocephala dominates the canopy and subcanopy layers. Exotic vines (Passiflora foetida and I pomea nil) and herbs (e.g. Cordia curassavica, euphorbia spp.) occur in the understorey. Seedlings of Leucaena often carpet the ground. I n some areas, scattered individuals of native forest species (Macaranga tanarius, Terminalia catappa, Gyrocarpus americanus and Claoxylon indicum) occur either as emergents or beneath the Leucaena canopy. These thickets are likely the result of high intensity and/ or repeated disturbances. 4 Shrubland-thicket-young secondary forest mosaic A mixed unit comprises scattered clumps of Macaranga tanarius 6 to 9m in height interspersed with: (a) shrublands areas dominated by Leucaena leucocephala and/ or Muntingia calabura and (b) closed to mid-dense fernlands of Nephrolepis multiflora. The Macaranga clumps frequently have an understorey of mature shrubs (Leucaena leucocephala, Claoxylon indicum and Pipturus argenteus) or occasionally young trees (Dysoxylon gaudichaudianum, Pittosporum ferrugineum, Planchonella nitida, Tristiropsis acutangula). Climbers and scramblers, including Passiflora foetida, Maclura conchinchinensis and I pomea species, are well represented. The ground layer is variable but often dominated by a mid-dense layer of ferns, especially Nephrolepis multiflora, Microsorium spp. and Davallia denticulata. 5 Macaranga secondary forest to 12m Regrowth forest of Macaranga tanarius 8 to 12m in height with a mid-dense to sparse canopy. A scattered midstratum of native and exotic shrubs and small trees is often present (e.g. Leucaena leucocephala, Pipturus argenteus and Claoxylon indicum). Ferns, especially Nephrolepis multiflora, Microsorium spp. and Davallia denticulata, form a dense ground layer where the canopy is sparse or senescent. This is a secondary successional vegetation characteristic of abandoned minefields in proximity to native forest boundaries. Also common in areas where the original vegetation has been cleared but not mined. 6 Advanced Macaranga secondary forest to 18m Well-developed secondary regrowth of Macaranga tanarius with mid-dense canopy to 18m in height. A sub-canopy layer is usually absent. The mid-stratum varies from dense to sparse and includes the early colonizing species present in map unit 5 above, but an increasing number of native forest species are also represented (e.g. Dysoxylon gaudichaudianum, Tristiropsis acutangula, Gyrocarpus americanus, Allophylus cobbe, Maclura Characteristic of Page 33 of 76 July 2020 Christmas Island vegetation surveys conchinchinensis). Occasional individuals of Planchonella nitida, I nocarpus fagifer, Barringtonia racemosa, Pandanus spp. and Arenga listeri are also found in this stratum in sheltered situations close to forest edges. This is a later successional stage of map unit 5 above. 7 Advanced mixed secondary forests Regrowth forest with a variable and uneven, mid-dense canopy to 22m often dominated by Macaranga tanarius. However, other native species (e.g. Dysoxylon gaudichaudianum, I nocarpus fagifer, Melia azedarach, Terminalia catappa) are also present depending on the disturbance history. Claoxylon indicum, Leea angulata, Pandanus sp., Pittosporum ferrugineum, Pisonia umbellata and Pipturus argenteus occur in the mid-stratum with occasional Hernandia ovigera, Planchonella nitida, Tristiropsis acutangula and Arenga listeri. The scramblers Maclura conchinchinensis and Schefflera actinophylla are also common. This is a later successional forest common in areas that have been cleared but not mined. 8 Deciduous & semi-deciduous vine thickets Open to dense thickets of native species with an uneven canopy 6 to 8m in height. Occasional emergents to 10m are present. Most emergent and canopy species are deciduous. Annual or perennial herbs are common in the ground layers. Dense thickets of evergreen Pandanus occur in some areas interspersed within the deciduous thickets. This vegetation type is common on inland cliffs and on exposed terrace areas on skeletal soils subject to severe seasonal water stress. 9 Semi-deciduous mesophyll vine forests Open to dense canopy of native species varying in height from 14 to 24m depending on soil depth and exposure. Deciduous emergent trees to 32m are common (e.g. Celtis timorensis, Gyrocarpus americanus, Terminalia catappa). Both deciduous and evergreen species occur in the canopy and mid-statum layers, but there is increasing dominance of deciduous species on thinner soils and more exposed sites. This is the typical native vegetation of terraces and exposed scree slopes. 10 Evergreen closed forests (Mesophyll vine forests & Complex mesophyll vine forests) Four forest structural types (CMVF + emergents, CMVF, MVF, MVF+ Ficus – see Table F3) that cannot be readily distinguished using aerial photography or satellite imagery are combined in this map unit. These are the most structurally complex native forests on the island and all occur on the plateau or sheltered areas of the upper terraces. They are characterized by evergreen, open to dense canopies which range from 18 to 40m in height depending on site oonditions (soil depth, exposure). Scattered very tall emergents (Hernandia ovigera, Planchonella nitida, Syzygium nervosum) to 50m are present on the deepest soils. Epiphytic ferns, orchids and climbers are common in these multi-strata forests. 11 12 Tree plantations Roads and bare clearings Plantings of horticultural and forest trees. Roads, tracks and cleared areas devoid of vegetation cover. Page 34 of 76 July 2020 Christmas Island vegetation surveys Table 7. Total areal extent of mapped vegetation types in the areas selected for possible future mining on Christmas Island (excluding areas considered not mineable because of topography or lithology). Note the following description for anthropogenic disturbance classes under SDMVF and Evergreen closed forest. 1. Some anthropogenic disturbance = scattered, low intensity damage e.g. localised understorey clearing 2. Significant anthropogenic disturbance= intense impacts in one or more strata of the vegetation e.g. drill-lines, timber harvesting Unit no. Vegetation type Total mineable area of each vegetation type in the selected areas ( ha) Vegetation types as % of total mineable area in the selected areas 1 Mixed shrublands 0.6 0.16 2 Muntingia shrublands 0.6 0.16 3 Leucaena thickets 1.0 0.26 4 Shrubland-thicket-young secondary forest mosaic 5.6 1.5 5 Macaranga secondary forest to 12m 0.4 0.10 6 Advanced Macaranga secondary forest to 18m 16.3 4.3 7 Advanced mixed secondary forests 28.2 7.4 8 Deciduous & semi-deciduous vine thickets 0.2 0.05 9 Semi-deciduous mesophyll vine forests Largely undisturbed Some anthropogenic disturbance Significant anthropogenic disturbance 13.9 3.8 0.1 3.6 1.0 0.03 Evergreen closed forests Largely undisturbed Some anthropogenic disturbance Significant anthropogenic disturbance 247.3 20.8 34.4 64.5 5.4 9.0 10 11 Plantations of trees and shrubs 1.1 0.3 12 Roads and bare clearings 8.9 2.3 Page 35 of 76 July 2020 Christmas Island vegetation surveys Table 8. Total area ( ha) of each vegetation type mapped in areas selected for possible future mining on Christmas I sland ( excluding areas considered not mineable because of topography or lithology). Note the following description for anthropogenic disturbance classes under SDMVF and Evergreen closed forest: 1. Some anthropogenic disturbance = scattered, low intensity damage e.g. localised understorey clearing. 2. Significant anthropogenic disturbance= intense impacts in one or more strata of the vegetation e.g. drill-lines, timber harvesting. Vegetation type ( map unit # ) MCI 70/ 8 MCI 70/ 9 MCI 70/ 10 MCI 70/ 11 MCI 70/ 12 MCI 70/ 13 MCI 70/ 14 MCI 70/ 15 MCI 70/ 16 TOTAL Mixed shrublands (1) - - 0.6 0.02 - - - - - 0.62 Muntingia shrublands (2) - - - - - 0.6 - - - 0.6 Leucaena thickets (3) - - - 0.6 - 0.4 - - - 1.0 Shrubland-thicket-young secondary forest mosaic (4) - - 0.2 5.4 - - - - - 5.6 Macaranga secondary forest to 12m (5) 0.2 - - - - 0.2 - - - 0.4 Advanced Macaranga secondary forest to 18m (6) 2.4 - 9.2 - 3.1 - 1.6 - - 16.3 Advanced mixed secondary forests (7) 4.7 11.4 7.9 - 1.6 - 2.6 - - 28.2 - - - - 0.2 - - - - 0.2 6.5 - - - 3.8 6.2 - - 1.2 - - 13.9 3.8 - - - - - - - 0.1 - - 0.1 - 82.6 2.1 90.2 - 16.5 14.6 - 3.6 1.6 - 38.8 2.5 11.6 - 4.0 - 247.3 20.8 3.6 3.6 8.9 - 3.8 8.9 - - - 3.3 0.9 0.9 - 0.5 - 21.0 13.4 - - - - - - - - 1.1 1.1 1.2 2.6 2.4 - - - 2.5 0.1 0.1 8.9 106.9 113.1 64.1 9.8 10.1 7.4 52.2 13.9 5.7 383.2 Deciduous & semi-deciduous vine thickets (8) Semi-deciduous mesophyll vine forests (9) Largely undisturbed Some anthropogenic disturbance Significant anthropogenic disturbance (a) Drill-lines (b) Other Evergreen closed forests (10) Largely undisturbed Some anthropogenic disturbance Significant anthropogenic disturbance (a) Drill-lines (b) Other Plantations of trees and shrubs (11) Roads and bare clearings TOTAL AREA/ LEASE ( ha) Page 36 of 76 July 2020 Christmas Island vegetation surveys Table 9. Summary of the extent and nature of previous anthropogenic disturbances of vegetation in areas selected for possible future mining. Lease MCI % of area affected by previous disturbance ( % previously cleared) 70/ 8 16 (7) 70/ 9 18 (10) 70/ 10 73 (28) 70/ 11 100 (61) 64 (49) 70/ 12 70/ 13 16 (16) 70/ 14 22 (8) 70/ 15 7 (0) 28 (20) 70/ 16 Description and comments on extent and intensity of existing disturbance Seventeen ha of this area has been subject to anthropogenic disturbance. More than half of this (9.3 ha) is disturbance in primary forest associated with development, exploration and drilling conducted by BPC. I n these areas the canopy of the forest is still largely intact and closed, although where drill-lines are present they are still clearly discernable on the ground and in some aerial photography. Regrowth vegetation which has established following clearing covers 7.3 ha, with most of this now being advanced secondary forests (of native species) that occur in areas in the vicinity of old minefields. These secondary forest areas were cleared but not mined (~ 7.1 ha). Weedy exotic vegetation is confined to narrow bands on road verges. There are frequent gaps created by natural treefalls in the SDMVF on the shallower soil in the south-western corner of the proposed lease. Natural tree fall gaps also occur in the CMVF, but at much lower frequency than in the more exposed SDMVF. About a fifth of this area has been disturbed in the past. Ten percent of the area has been previously cleared (all of which is adjacent to old minefields) and advanced mixed secondary forests now predominate in these locations. Drill-lines cleared into the forest cover about 8% of the proposed lease. This area has been the subject of significant past disturbance both for mining and for infrastructure development. There are small areas of weed infested shrublands and regrowth mosaics (~ 0.8 ha) and approximately 17 ha of secondary forest in the east of the lease. Although evergreen closed forests cover two thirds of the area, only 38% of this is largely undisturbed. The rest has been subjected to varying intensities of disturbance associated with exploration and perhaps timber gathering. This area is highly disturbed. Although natural vegetation (primarily SDMVF) covers 39% of the mineable area almost all of this has been disturbed to some degree. Regrowth dominated by exotic species is a feature of much of the vegetation in this lease. The western part of this area that fringes old minefields has been extensively disturbed and comprises advanced secondary forests on stockpiled materials and on areas that have been cleared but not mined. The eastern section of this lease is largely undisturbed natural forest but much has been excluded as unmineable because of the steep topography and/ or skeletal soils. A narrow band in the western part of this area that fringes an old minefield has been extensively disturbed and is colonized by weedy regrowth vegetation. The remainder of the vegetation is SDMVF and appears to have not been subjected to significant anthropogenic disturbance. However, much of this forest is on sloping terrain and is exposed to the east and southeast. The forest canopy and structure in these areas is very uneven and there are frequent large canopy gaps associated with natural treefalls. There is evidence of colonization, albeit at low density, into the understorey of these native forest area by exotic weeds (e.g. Leucaena leucocephala, Turnera procumbens). A relatively undisturbed area with advanced secondary forests on cleared areas and stockpiles fringing adjoining old minefields and roads. Evergreen closed forest covers more than 90% of this lease (~ 45ha), with 7 ha of this having been subject to disturbance. Most of this disturbance is associated with exploration drill-lines and areas of understorey clearing. Some of the natural forest on the central north boundary of this lease that occurs in proximity to an existing minefield has significant recent treefall gaps. Although dominated by natural forest, about 7% of this area has been disturbed by exploration drill-lines that are at high densities in some localized areas. A small 4 ha patch of relatively undisturbed forest occurs in the centre of this lease area. The immediate surrounds of this patch are native forest but have been disturbed, the canopy in these areas is largely intact but the understorey and mid-strata have been significantly affected. The north of this area comprises a plantation of exotic timber and fruit trees planted by BPC. Page 37 of 76 July 2020 Christmas Island vegetation surveys Table 10. List of species found in major vegetation types in areas selected for possible future mining. Note that map units 1 to 4 are regrowth shrublands and thickets while map units 5 to 7 are secondary forests. ‘Gaps in MVF/CMVF’ refers to species found in tree falls, drill-lines and similar light gaps in these normally closed forest types. 0=species not recorded, 1= species present. Species names highlighted in bold are currently listed under the EPBC Act; those underlined are endemic to Christmas Island. Nomenclature for species follows Du Puy (1993). LI FEFORM MAP UNI TS 1-4 MAP UNI TS 5-7 DVT UNI T 8 SDMVF UNI T 9 MVF UNI T 10 CMVF UNI T 10 Gaps in MVF/ CMVF introduced herb 1 0 0 0 0 0 0 Rutaceae native tree 0 0 1 1 1 0 0 Ageratum conyzoides Asteraceae introduced herb 1 0 0 0 0 0 0 Aidia racemosa Rubiaceae native shrub 0 0 1 1 1 1 1 Alchornea rugosa Euphorbiaceae native shrub 0 1 0 1 1 1 1 Allophyllus cobbe Sapindaceae native shrub 0 1 1 1 1 1 1 SPECI ES FAMI LY STATUS Acalphya indica Euphorbiaceae Acronychia trifoliata Alternanthera pungens Amaranthaceae introduced herb 1 0 0 0 0 0 0 Amaracarpus pubescens Rubiaceae native shrub 0 0 0 0 0 1 0 Antigonon leptopus Polygonaceae introduced vine 1 0 0 0 0 0 0 Ardisia colorata Myrsinaceae native shrub 0 0 0 0 1 1 1 Arenga listeri Arecaceae native palm 0 1 1 1 1 1 1 Arthropteris palisotti Davalliaceae native fern 0 0 0 0 1 1 0 Asplenium listeri Aspleniaceae fern fern 0 0 1* 0 0 0 0 Asplenium nidus Aspleniaceae native native 0 1 0 1 1 1 0 Asplenium polyodon Aspleniaceae native fern 0 0 0 1 1 1 0 Aster subulatus Asteraceae introduced herb 1 0 0 0 0 0 0 Barringtonia racemosa Lecythidaceae native tree 0 1 0 1 1 1 1 Berrya cordifolia Tiliaceae native tree 0 0 0 1 1 0 0 Bidens pilosa Asteraceae introduced herb 1 0 0 0 0 0 0 Blumea balsamifera Asteraceae native herb 0 1 0 0 0 0 0 Bolbitis heteroclita Lomariopsidaceae native fern 0 0 0 0 1 1 1 Brachiaria reptans Poaceae introduced grass 1 0 0 0 0 0 0 Brachypeza archytas Orchidaceae native orchid 0 0 0 1 1 1 0 Bryobium pubescens Orchidaceae native orchid 0 0 0 0 1 1 0 Caesalpinia spp. Caesalpiniaceae native shrub 0 0 0 1 0 0 0 Callicarpa longifolia Verbenaceae native shrub 0 0 0 1 0 0 1 Capsicum anuum Solanaceae introduced herb 1 0 0 0 0 0 38 of 76 Page 0 July 2020 Christmas Island vegetation surveys LI FEFORM MAP UNI TS 1-4 MAP UNI TS 5-7 DVT UNI T 8 SDMVF UNI T 9 MVF UNI T 10 CMVF UNI T 10 Gaps in MVF/ CMVF introduced herb 1 0 0 0 0 0 0 Caricaceae introduced tree 1 0 0 0 0 0 0 Boraginaceae native shrub 0 1 1 1 0 0 0 SPECI ES FAMI LY STATUS Cardiospermum halicacabum Sapindaceae Carica papaya Carmona retusa Cayratia japonica Vitaceae native vine 0 0 0 1 1 0 0 Cayratia pedata Vitaceae native vine 1 1 1 1 0 0 0 Celastrus paniculatus Celastraceae native vine 0 1 1 1 1 1 1 Celtis timorensis Ulmaceae native tree 0 0 0 1 1 1 1 Cenchrus brownii Poaceae introduced grass 1 0 0 0 0 0 0 Centrosema pubescens Fabaceae introduced vine 1 0 0 0 0 0 0 Chloris barbata Poaceae introduced grass 1 0 0 0 0 0 0 Christella subpubescens Thelypteridaceae native fern 0 0 0 0 0 0 1 Cissus repens Vitaceae native vine 0 1 0 1 1 1 1 Claoxylon indicum Euphorbiaceae native tree 0 1 0 1 1 0 1 Clausena excavata Rutaceae introduced tree 1 1 1 1 1 0 1 Colubrina pedunculata Rhamnaceae native tree 0 0 1 1 0 0 0 Combretum acuminatum Combretaceae native shrub 0 1 0 1 1 1 1 Conyza bonariensis Asteraceae introduced herb 1 0 0 0 0 0 0 Cordia curassavica Boraginaceae introduced shrub 1 0 1 0 0 0 0 Corymborkis veratrifolia Orchidaceae native orchid 0 0 0 0 1 1 1 Crassocephalum crepidioides Asteraceae introduced herb 1 0 0 0 0 0 0 Crinum asiaticum Liliaceae native herb 0 0 0 1 0 0 0 Croton caudatus Euphorbiaceae native vine 0 0 1 1 0 0 0 Cryptocarya nitens Cyperus sp. Davallia denticulata Davallia solida Lauraceae Cyperaceae Davalliaceae Davalliaceae native introduced native native tree rush fern fern 0 1 1 0 0 0 1 0 0 1 0 0 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 1 Deeringia amaranthoides Amaranthaceae native vine 0 0 0 1 0 0 0 Dendrobium crumenatum Orchidaceae native orchid 0 0 0 1 1 1 0 Dendrocnide peltata Urticaceae native tree 0 0 1 0 0 0 0 Dendrocnide sinuata Urticaceae native tree 0 0 0 1 0 0 1 Desmodium triflorum Fabaceae introduced herb 1 0 0 0 0 0 0 Page 39 of 76 July 2020 Christmas Island vegetation surveys LI FEFORM MAP UNI TS 1-4 MAP UNI TS 5-7 DVT UNI T 8 SDMVF UNI T 9 MVF UNI T 10 CMVF UNI T 10 Gaps in MVF/ CMVF native tree 0 1 0 1 1 1 1 Boraginaceae native tree 0 0 0 0 0 1 0 Poaceae introduced grass 1 0 0 0 0 0 0 SPECI ES FAMI LY STATUS Dysoxylon gaudichaudianum Meliaceae Ehretia javanica Eleusine indica Emilia sonchifolia Asteraceae introduced herb 1 0 0 0 0 0 0 Eragrostis pilosa Poaceae introduced grass 1 0 0 0 0 0 0 Euphorbia cyathophora Euphorbiaceae introduced herb 1 0 0 0 0 0 0 Euphorbia heterophylla Euphorbiaceae introduced herb 1 0 0 0 0 0 0 Euphorbia hirta Euphorbiaceae introduced herb 1 0 0 0 0 0 0 Euphorbia prostrata Euphorbiaceae introduced herb 1 0 0 0 0 0 0 Ficus microcarpa Moraceae native tree 0 1 0 1 1 1 1 Ficus saxophila Moraceae native tree 0 0 0 1 0 0 0 Fimbristylis cymosa Cyperaceae native rush 1 0 0 0 0 0 0 Flickingeria nativitatis Orchidaceae native orchid 0 0 0 1 1 1 0 Galactia tenuiflora Fabaceae native vine 0 0 1 1 0 0 0 Grewia acuminata Tiliaceae native shrub 0 0 1 1 0 0 0 Grewia glabra Tiliaceae native shrub 0 0 1 0 0 0 0 Grewia insularis Tiliaceae native tree 0 0 1 1 0 0 0 Guettarda speciosa Rubiaceae native tree 0 1 1 1 1 0 1 Gyrocarpus americanus Hernandiaceae native tree 0 1 0 1 0 0 0 Hernandia ovigera Hernandiaceae native tree 0 0 0 0 1 1 1 Hoya aldrichii Asclepidaceae native vine 0 1 1 1 1 1 1 I lligera appendiculata Hernandiaceae native vine 0 0 0 1 0 0 0 I nocarpus fagifer Fabaceae native tree 0 1 0 1 1 1 1 I pomoea spp. Convolvulaceae introduced vine 1 0 0 0 0 0 0 Kleinhovia hospita Sterculiaceae native tree 0 0 1 1 0 0 0 Leea angulata Leeaceae native shrub 0 1 1 1 1 0 1 Leptochilus decurrens Polypodiaceae native fern 0 0 0 0 0 1 1 Leucaena leucocephala Mimosaceae introduced shrub 1 1 1 1 0 0 0 Leucas flaccida Lamiaceae native herb 1 0 0 0 0 0 0 Ligustrum glomeratum Oleaceae native shrub 0 0 0 1 0 0 0 Macaranga tanarius Euphorbiaceae native tree 1 1 0 1 0 0 1 Page 40 of 76 July 2020 Christmas Island vegetation surveys LI FEFORM MAP UNI TS 1-4 MAP UNI TS 5-7 DVT UNI T 8 SDMVF UNI T 9 MVF UNI T 10 CMVF UNI T 10 Gaps in MVF/ CMVF native vine 1 1 1 1 1 1 1 Fabaceae introduced vine 1 0 0 0 0 0 0 Euphorbiaceae introduced shrub 1 0 0 0 0 0 0 SPECI ES FAMI LY STATUS Maclura cochinchinensis Moraceae Macroptilium atropurpureum Manihot glazvoii Melia azedarach Meliaceae native Melinis repens Poaceae introduced tree 0 1 0 1 0 0 0 grass 1 0 0 0 0 0 0 Melochia umbellata Sterculiaceae native tree 0 1 1 1 1 0 1 Microlepia speluncae Dennstaedtiaceae native fern 0 0 0 0 0 0 1 Microsorum punctatum Polypodiaceae native fern 0 1 0 1 1 1 0 Microsorum scolopendria Polypodiaceae native fern 1 1 0 1 0 0 0 Mimosa invisa Mimosaceae introduced shrub 1 0 0 0 0 0 0 Mimosa pudica Mimosaceae introduced shrub 1 1 0 0 0 0 0 Muntingia calabura Flacourtiaceae introduced shrub 1 0 0 0 0 0 0 Nephrolepis biserrata Davalliaceae native fern 0 1 0 1 1 1 1 Nephrolepis multiflora Davalliaceae native fern 1 1 0 1 0 0 0 Ochrosia ackeringae Apocynaceae native tree 0 0 1 1 1 0 0 Pachygone ovata Menispermaceae native vine 0 1 1 1 1 1 1 Pandanus christmatensis Pandanaceae native palm 0 0 1 0 0 0 0 Pandanus elatus Pandanaceae native palm 0 1 0 1 1 1 1 Passiflora foetida Passifloriaceae introduced vine 1 1 1 0 0 0 0 Phreatia listeri Orchidaceae native orchid 0 0 0 0 1 1 0 Phyllanthus amarus Euphorbiaceae introduced herb 1 0 1 0 0 0 0 Physalis pubescens Solanaceae native herb 1 1 0 1 0 0 0 Pipturus argenteus Urticaceae native tree 0 1 0 1 1 1 1 Pisonia grandis Nyctaginaceae native tree 0 0 0 1 0 0 0 Pisonia umbellifera Nyctaginaceae native tree 0 1 0 1 1 1 1 Pittosporum ferrugineum Pittosporaceae native tree 0 1 0 1 1 0 1 Pityrogramma calomelanos Adiantaceae introduced fern 1 0 0 0 0 0 0 Planchonella nitida Sapotaceae native tree 0 1 0 1 1 1 1 Pongamia pinnata Fabaceae native tree 0 1 1 1 0 0 0 Premna lucidula Verbenaceae native tree 0 0 0 1 0 0 0 Procris pedunculata Urticaceae native shrub 0 0 0 0 1 0 1 Page 41 of 76 July 2020 Christmas Island vegetation surveys LI FEFORM MAP UNI TS 1-4 MAP UNI TS 5-7 DVT UNI T 8 SDMVF UNI T 9 MVF UNI T 10 CMVF UNI T 10 Gaps in MVF/ CMVF shrub 1 1 0 0 0 0 0 native fern 1 1 0 0 0 0 0 native fern 0 0 0 0 1 0 1 SPECI ES FAMI LY STATUS Psidium guajava Myrtaceae introduced Psilotum nudum Psilotaceae Pteris tripartita Pteridaceae Pteris vittata Pteridaceae native fern 1 1 1 0 0 0 0 Pteridrys syrmatica Dryopteridaceae native fern 0 0 0 0 1 1 1 Pyrrosia lanceolata Polypodiaceae native fern 1 1 1 1 1 1 1 Quisqualis indica Combretaceae native vine 0 0 0 1 0 0 0 Schefflera elliptica Araliaceae native vine 0 1 1 1 1 1 1 Sida spp. Malvaceae introduced herb 1 0 1 0 0 0 0 Spermococe assurgens Rubiaceae introduced herb 1 0 0 0 0 0 0 Stachytarpheta jamaicensis Verbenaceae introduced herb 1 1 0 0 0 0 0 Stylosanthes humilis Fabaceae introduced herb 1 0 1 0 0 0 0 Syzygium nervosum Myrtaceae native tree 0 0 0 1 1 1 1 Tecoma stans Asteraceae introduced shrub 1 0 0 0 0 0 0 Tectaria devexa var minor Dryopteridaceae native fern 0 0 0 0 0 1 1 Tectaria dissecta Dryopteridaceae native fern 0 0 0 0 0 1 1 Terminalia catappa Combretaceae native tree 0 1 0 1 1 1 0 Thrixspermum carinatifolium Orchidaceae native orchid 0 0 0 0 0 1 0 Tithonia diversifolia Asteraceae introduced herb 1 0 0 0 0 0 0 Trema tomentosa Ulmaceae introduced tree 1 1 0 0 0 0 0 Tridax procumberns Asteraceae introduced herb 1 0 0 0 0 0 0 Tristiropsis acutangula Sapindaceae native tree 0 1 0 1 1 1 1 Turnera procumbens Turneraceae introduced herb 1 1 1 1 0 0 0 Urena lobata Malvaceae native herb 0 1 1 1 0 0 0 Urochloa mosambicensis Poaceae introduced grass 1 0 0 0 0 0 0 Vernonia cinerea Asteraceae introduced herb 1 0 0 0 0 0 0 Vittaria elongata Vittariaceae native fern 0 1 0 0 1 1 1 61 52 37 73 54 48 48 TOTAL NUMBER OF SPECI ES RECORDED PER VEGETATI ON TYPE Page 42 of 76 July 2020 Christmas Island vegetation surveys Table 11. Summary of key floristic features of major vegetation mapping units used in this survey. Note that all four regrowth shrubland/ shrub-thicket units have been combined, as have the three secondary forest units. Vegetation Map Unit 1-4 5-7 8 9 10 Total no. species 61 52 37 73 65 No. native species 13 44 29 69 64 No. naturalized species 48 8 8 4 1 % naturalized species 79 15 22 5 2 No. tree species 4 19 10 31 26 No. shrub species 8 8 8 11 9 No. vine species 7 8 10 14 6 No. fern species 7 10 3 9 16 No. orchid species 0 0 0 3 7 37 0 11 17 16 No. species restricted to each map unit ‘I ndicator’ species restricted to specific vegetation map units in this survey Unit 10 – Evergreen closed forests TREES SHRUBS GROUNDLAYER EPI PHYTES Ehretia javanica Hernandia ovigera Amaracarpus pubescens Ardisia colorata Procris pedunculata Arthropteris palisotti Bolbitis heteroclita Christella subpubescens Corymborkis veratrifolia Leptochilus decurrens Microlepia speluncae Pteridrys syrmatica Tectaria devexa Tectaria dissecta Bryobium pubescens Phreatia listeri Unit 9 – Semi-deciduous mesophyll vine forest TREES SHRUBS VI NES Gyrocarpus americanus Melia azedarach Pisonia grandis Caesalpinia sp. Ligustrum glomerata Deeringia amaranthoides I lligera appendiculata Quisqualis indica Unit 8 – Deciduous vine thicket TREES SHRUBS Dendrocnide peltata Grewia glabra Pandanus christmatensis Page 43 of 76 July 2020 Christmas Island vegetation surveys Table 12. Summary of structural features of vegetation in quantitative survey plots established in areas selected for possible future mining. Plot no. Canopy height ( m) Max. height of emergents ( m) No. of tree species present ( > 5cm DBH) Basal area/ ha ( All trees > 5cm DBH) Stem densities ( No. trees/ ha DBH > 5cm) % basal area in trees > 50cm DBH 18 to 24m 20 to 26m 22 to 26m 30m 18 to 22m 26m 30m 40m 44m n/ a 9 8 11 7 8 28.1 89.7 101.3 85.5 66.2 825 1000 1178 583 1300 22 59 75 83 33 8.6 SDMVF CMVF CMVF + emergents CMVF + emergents Advanced secondary regrowth MVF 20 to 26m 30m 12 79.3 1350 56 9.1 9.2 9.3 9.4 CMVF CMVF CMVF on limestone MVF + Ficus 30 30 24 20 34m 34m 32m 28m 38m 40m 40m 32m 8 8 10 9 92.0 100.9 51.2 49.3 875 1175 1075 675 81 82 68 60 10.1 10.2 10.3 10.4 CMVF CMVF CMVF Macaranga secondary forest 28 to 36m 24 to 28m 24 to 28m 9m 40m 32m 36m n/ a 10 7 11 5 85.4 132.2 74.4 12.2 875 750 1200 1850 86 88 78 0 11.1 11.2 DVT SDMVF 6 to 7m 16 to 20m 9m 24m 4 7 24.1 49.0 1950 1333 0 47 12.1 12.2 12.3 12.4 SDMVF MVF + Ficus CMVF SDMVF/ DVT 16 18 24 10 20m 22m 28m 14m 24m 28m 32m 16m 6 10 8 7 40.2 55.3 98.1 57.0 1000 725 1075 1450 56 67 80 63 13.1 13.2 13.3 SDMVF SDMVF SDMVF 12 to 16m 8 to 16m 8 to 12m 18m 24m 16m 9 10 15 42.1 46.2 21.4 1350 650 1125 71 61 31 14.1 CMVF 26 to 30m 36m 7 80.2 700 67 8.1 8.2 8.3 8.4 8.5 Vegetation structural type to to to to to to to to Page 44 of 76 July 2020 14.2 14.3 14.4 14.5 14.6 14.7 14.8 14.9 Christmas Island vegetation surveys 24 24 20 18 12 16 20 14.10 14.11 14.12 CMVF CMVF + emergents CMVF MVF SDMVF CMVF CMVF + emergents Mixed secondary regrowth CMVF CMVF CMVF to 32m to 30m to 26m to 22m to 20m to 28m to 24m 14m 36m 40m 30m 30m 28m 32m 42m n/ a 9 8 10 12 7 7 10 6 76.5 87.6 50.8 51.1 63.2 79.8 98.9 18.1 725 575 700 1150 950 1250 775 2100 82 88 70 41 67 61 78 0 26 to 32m 24 to 28m 24 to 28m 35m 32m 32m nd 10 nd nd 92.3 nd nd 975 nd nd 78 nd 15.1 15.2 15.3 SDMVF MVF CMVF 12 to 22m 18 to 24m 20 to 22m 26m 28m 30m 5 7 10 58.5 62.8 80.7 350 525 875 88 72 75 Page 45 of 76 July 2020 Christmas Island vegetation surveys Table 13. Summary of descriptive statistics for a range of structural features of vegetation from quantitative floristic survey plots. Values separated by ± are means and standard deviations; values in brackets are medians followed by the range in values recorded. Vegetation structural type DVT SDMVF MVF & MVF + Ficus CMVF CMVF + emergents Plot no. Canopy height ( m) Height of emergents ( m) No. of tree species present ( > 5cm DBH) Basal area/ ha ( All trees > 5cm DBH) Stem densities ( No. trees/ ha DBH > 5cm) % basal area in trees > 50cm DBH 11.1 7 9 4 24.1 1950 0 8.1, 11.2, 12.1, 12.4, 13.1,13.2, 13.3, 14.6,15.1 8.6, 14.5, 15.2 9.4, 12.2 18 ± 4 (20, 12-24) 22 ± 5 (24, 16-28) 8.3 ± 3.0 (7, 5-15) 45 ± 14 (46, 21-63) 1005 ± 360 (1000, 350-1450) 56 ± 20 24 ± 3 (24, 22-28) 30 ± 2 (30, 28-32) 10.0 ± 2.1 (10, 7-12) 62 ± 11 (63, 49-79) 945 ± 330 (975, 525-1350) 59 ± 14 8.2, 9.1, 9.2, 9.3, 10.1, 10.2,10.3, 12.3, 14.1, 14.2, 14.4, 14.7, 14.10, 14.11, 14.12, 15.3 8.3, 8.4, 14.3, 14.8 30 ± 4 (29, 22-36) 35 ± 4 (35, 30-40) 8.8 ± 1.4 (8.5, 7-10) 85 ± 20 (83, 51-132) 945 ± 190 (925, 700-1250) 76 ± 8 28 ± 3 (28, 24-30) 42 ± 2 (41, 40-44) 9 ± 1.8 (9, 7-11) 93 ± 8 (93, 85-101) 780 ± 280 (680, 580-1180) 81 ± 6 Page 46 of 76 July 2020 Christmas Island vegetation surveys Table 14. Summary of the distribution and intensity of sampling in different regions and vegetation types on Christmas Island by Holmes and Holmes (2002). Note that calculation of the areas of each vegetation type are based on data from CI GIS, while plot locations were derived from GPS coordinates provided by DEH. ( a) Total area ( ha) of each vegetation type in each sector of the I sland TOTAL Vegetation type Western Central Northeast Southeast (per veg. type) 3006 Tall closed forest, deep soil phase 324 889 1013 781 Closed forest, shallow soil phase 1162 834 1209 1227 4432 Closed forest, scree/ pinnacle phase 836 559 677 551 2624 Open forest, and vine woodland 63 0 66 53 183 Closed forest, freshwater seepage 6 0 12 0 18 Heath, shrubland, low closed woodland 50 49 58 67 225 Natural and planted revegetation 273 424 1365 1091 3152 ( b) Number of survey sites in each vegetation type in each sector TOTAL Vegetation type Western Central Northeast Southeast (per veg. type) Tall closed forest, deep soil phase 18 40 21 22 101 Closed forest, shallow soil phase 71 10 21 18 120 Closed forest, scree/ pinnacle phase 41 29 11 16 97 Open forest, and vine woodland 21 0 1 1 23 Closed forest, freshwater seepage 2 0 0 0 2 Heath, shrubland, low closed woodland 3 0 17 5 25 Natural and planted revegetation 4 4 14 15 37 160 83 85 77 405 TOTAL ( c) I ntensity of survey sites in each vegetation type (no. of sites per 100 ha of each vegetation type in each sector) Average Vegetation type Western Central Northeast Southeast Tall closed forest, deep soil phase 5.6 4.5 2.1 2.8 3.4 Closed forest, shallow soil phase 6.1 1.2 1.7 1.5 2.7 (per veg. type) Closed forest, scree/ pinnacle phase 4.9 5.2 1.6 2.9 3.7 Open forest, and vine woodland 33.1 n/ a 1.5 1.9 12.6 Closed forest, freshwater seepage 34.1 n/ a 0 n/ a 11.4 Heath, shrubland, low closed woodland 6.0 0 29.4 7.5 11.1 Natural and planted revegetation 1.5 0.9 1.0 1.4 1.2 AVERAGE sampling intensity per sector 5.9 3.0 1.9 2.0 3.0 Page 47 of 76 July 2020 Christmas Island vegetation surveys Table 15. Distribution and population sizes of plant species of conservation significance on sites surveyed by Holmes and Holmes (2002). Data are summarised from confidential site information provided by DEH. Species Records Status Sector: No. sites (No. individuals) Current EPBC-listed species Asplenium listeri EPBC -- Endangered (H&H - Endangered) Western: 1 (6) Central: 1 (100) Northeastern: 2 (200) Pneumatopteris truncata EPBC – Endangered (H&H - Endangered) Western: 1 (30) Central: 3 (34) Tectaria devexa var minor EPBC – Endangered (H&H -- Rare) Western: 9 (381) Central: 3 (16) Southeastern: 4 (9) Carmona retusa EPBC -- Vulnerable (H&H -- Not listed) No data recorded – not considered of conservation significance by H&H Species recommended for EPBC listing Asystasia alba H&H -- Endangered Western: 5 (200) Dicliptera maclearii H&H -- Endangered 0 Muellerargia timorensis H&H -- Endangered Western: 6 (109) Blumea lanceolaria H&H -- Endangered Central: 1 (7) Cycas rumphii H&H -- Vulnerable Western: 1 (2) Northeastern: 1 (3) Spondias cytherea H&H -- Vulnerable Western: 1 (207) Northeastern: 2 (12) Southeastern: 1 (1) Dendrocnide peltata var. murrayana H&H -- Vulnerable Western: 6 (24) Northeastern: 2 (4) Other species of conservation significance) Amaracarpus pubescens H&H -- Rare Western: 1 (10) Southeastern: 1 (10) Abelmoschus manihot H&H -- Rare Western: 1 (1) Southeastern: 2 (6) Abutilon listeri H&H -- Rare Western: 15 (186) Central: 1 (10) Northeastern: 20 (319) Southeastern: 10 (293) Balanophora abbreviata H&H -- Rare Western: 1 (100) Blumea balsamifera H&H – Poorly known Bryobium pubescens H&H -- Rare Cinnamomum iners H&H – Poorly known 0 Western: 7 (610) Central: 12 (1,690) Northeastern: 8 (1,480) Southeastern: 6 (800) 0 Page 48 of 76 July 2020 Christmas Island vegetation surveys Cleome gynandra H&H -- Rare 0 Colubrina pedunculata H&H -- Rare Western: 24 (1,673) Northeastern: 6 (35) Commicarpus chinensis H&H -- Rare 0 Cynometra ramiflora H&H -- Rare Southeastern: 4 (152) Didymoplexis pallens H&H -- Rare 0 Ficus saxifolia H&H -- Rare Western: 24 (66) Central: 1 (1) Northeastern: 6 (7) Southeastern: 5 (9) Flickingeria nativitatis H&H -- Rare Western: 30 (18,360) Central: 42 (18,840) Northeastern: 18 (8,170) Southeastern: 9 (2,060) Grewia insularis H&H -- Rare Western: 17 (42) Central: 1 (5) Northeastern: 7 (18) Huperzia phlegmaria H&H -- Rare Western: 1 (1) Central: 1 (1) Southeastern: 1 (4) I lligera elegans H&H -- Rare Western: 10 (11) Northeastern: 4 (4) I schaemum nativitatis H&H -- Rare Western: 2 (11) Northeastern: 2 (57) Jacquemontia paniculata H&H – Poorly known 0 Leucas zeylandica H&H -- Rare Northeastern: 1 (12) Southeastern: 1 (2) Leptochilus decurrens H&H – Rare Western: 1 (20) Central: 2 (70) Southeastern: 4 (158) Lycianthes biflora H&H – Rare 0 Momordica charantia H&H – Rare 0 Mucuna pruriens H&H – Rare 0 Peperomia laevifolia H&H – Poorly known 0 Peperomia rossi H&H – Poorly known 0 Phreatia listeri H&H – Rare Western: 6 (66) Central: 13 (1,721) Northeastern: 10 (1,290) Southeastern: 7 (120) Pteridrys syrmatica H&H – Rare Western: 10 (46) Central: 10 (87) Northeastern: 2 (6) Southeastern: 3 (24) Remusatia vivipara H&H – Rare 0 Selaginella alutacia H&H – Poorly known 0 Setaria clivalis H&H – Poorly known 0: H&H – Rare 0 Spermacoce mauritiana Page 49 of 76 July 2020 Christmas Island vegetation surveys Strongylodon lucidus H&H – Rare Taeniophyllum hasseltii H&H – Rare Tectaria devexa var minor H&H – Rare Western: 9 (381) Central: 3 (16) Southeastern: 4 (9) Tectaria dissecta H&H – Rare Western: 12 (149) Central: 14 (30) Northeastern: 4 (4) Southeastern: 14 (61) Tectaria sp. H&H – Poorly known Western: 4 (14) Central: 2 (4) Northeastern: 1 (1) Southeastern: 6 (26) Western: 1 (1) Central: 2 (8) Southeastern: 1 (10) Southeastern: 3 (9) Thelasis capitata H&H – Rare Central: 2 (200) Thrixspermum carinatifolia H&H – Rare Western: 16 (127) Central: 22 (775) Northeastern: 12 (156) Triphasia trifolia H&H – Rare 0 Triumfetta suffruticosa H&H – Rare 0 Vitis flexuosa H&H -- Rare Central: 3 (17) Zehneria alba H&H – Poorly known 0 Zeuxine exilis H&H – Poorly known 0 Page 50 of 76 July 2020 Christmas Island vegetation surveys Table 16. Occurrence of species of conservation significance on sites surveyed by Holmes and Holmes (2002) on, or within 100m of, areas selected for possible future mining. ( a) Total number of sites inside or w ithin 100m of the boundaries of areas selected for possible future mining No. of sites Within selected area Outside selected area, but Area ID boundaries within 100m of boundaries MCI 70/ 8 11 5 MCI 70/ 9 4 2 MCI 70/ 10 1 0 MCI 70/ 11 0 2 MCI 70/ 12 0 2 MCI 70/ 15 3 2 19 13 TOTAL ( b) Occurrence of species of conservation significance inside or w ithin 100m of the boundaries of the selected areas. Data are number of sites and total number of individuals. Area ID Records Conservation status No. of sites (No. of individuals) Within selected area boundaries Outside selected area, but w ithin 100m of boundaries H&H -- Rare 1 (50) - Flickingeria nativitatis* H&H – Rare 3 (1300) 2 (60) Leucas zeylanica H&H – Rare - 1 (2) Leptochilus decurrens* H&H – Rare 4 (158) - Phreatia listeri* H&H – Rare 2 (50) - H&H – Rare EPBC – Vulnerable H&H -- Rare H&H -- Rare - 1 (1) - 1 (6) 7 (16) - Bryobium pubescens* H&H – Rare 1 (50) - Tectaria dissecta* H&H – Rare 2 (2) 1 (1) Species MCI 70/ 8 Bryobium pubescens* Strongylodon lucidus Tectaria devexa var. minor* Tectaria dissecta* MCI 70/ 9 MCI 70/ 10 Bryobium pubescens* H&H – Rare 1 (500) - Flickingeria nativitatis* H&H – Rare 1 (50) - Phreatia listeri* H&H – Rare 1 (10) - H&H – Rare - 1 (2) H&H – Vulnerable - 1 (11) MCI 70/ 11 Abutilon listeri Spondias cytherea MCI 70/ 12 Page 51 of 76 July 2020 Christmas Island vegetation surveys Abutilon listeri H&H – Rare - 1 (6) Colubrina pedunculata* H&H -- Rare - 1 (20) Grewia insularis* H&H – Rare - 1 (10) H&H -- Rare 1 (10) - MCI 70/ 15 Amaracarpus pubescens* Bryobium pubescens* H&H – Rare - 1 (300) Flickingeria nativitatis* H&H – Rare 2 (550) 1 (100) Phreatia listeri* H&H -- Rare 2 (30) - * = also recorded on lease in EWLS survey for this EI S Page 52 of 76 July 2020 Christmas Island vegetation surveys Table 17: Details of locations at w hich plant species considered ‘rare’ or ‘poorly- know n’ by Holmes & Holmes ( 2002) w ere recorded during this survey. Unless indicated with an asterisk, species are categorised as Rare by Holmes & Holmes, * = a ‘poorly-known’ species. Endemic species are underlined. For details of location of individual (a) transects and plots see Figures 7 to 9 and (b) survey blocks see Figures 12 and 13. Species Habit Locations recorded in areas selected for possible future mining No. of populations ( individuals) Primarily in evergreen closed forests ( CMVF & MVF) Amaracarpus pubescens Shrub MCI 70/ 9: Transect 9F; Plot 9.1 MCI 70/ 15: Transect 15A 2 (6) 1 (1) Leptochilus decurrens Fern MCI 70/ 8: Transects 8A, C & D MCI 70/ 9: Transects 9A & F; Survey D5 MCI 70/ 14: Transect 14A; Survey D9 3 (5) 3 (3) 1 (2) Pteridrys syrmatica Fern MCI 70/ 9: Transects 9A & 9F 3 (4) Tectaria devexa var minor Fern MCI 70/ 8: Survey D11 1 (1) Fern MCI 70/ 8: Transects 8C, D, G & H; Survey D18 & D20 MCI 70/ 9: Transects 9B & F MCI 70/ 14: Transect 14B Tectaria dissecta 5 (> 20) 2 (7) 1 (2) More w idespread from CMVF to SDMVF Bryobium pubescens Orchid Most transects MCI 70/ 8, 9, 10, 12, 14, 16 Numerous Flickingeria nativitatis Orchid Most transects MCI 70/ 8, 9, 10, 12, 14, 15, 16 Numerous Phreatia listeri Orchid Most transects MCI 70/ 8, 9, 10, 12, 14, 15, 16 Numerous Ficus saxifolia Tree Thrixspermum carinatifolia Orchid MCI 70/ 13: Survey B5 MCI 70/ 9: Transect 9B; Survey D5 1 (2) 2 (> 5) SDMVF & DVT Colubrina pedunculata Grewia insularis Tree Shrub MCI 70/ 11: Transect 11A, Plot 11.1; Survey B1 MCI 70/ 13: Transects 13A & B; Plots 13.2 & 13.3; Survey B6 & B7 MCI 70/ 11: Transect 11A, Plot 11.1 MCI 70/ 13: Transects 13A & B; Plots 13.3; Survey B6 & B7 1 (> 10) 1 (> 10) 1 (5) 1 (> 10) Disturbed areas ( clearings & forest margins) * Blumea balsamifera Shrub MCI 70/ 9: Transect 9E (gap in Macaranga regrowth) 1 (1) Page 53 of 76 July 2020 Christmas Island vegetation surveys Table 18: Total areal extent of each of the mapped vegetation types in areas selected for possible future mining on Christmas I sland. Map unit no. Vegetation type Total mineable area of each vegetation type in the proposed areas ( ha) Gross area of each vegetation type potentially disturbed by mining after exclusion of protected areas and buffer zones ( ha) Estimated area of each vegetation type in selected areas follow ing successful rehabilitation ( ha) Net change in vegetation types in selected areas follow ing mining and successful rehabilitation ( ha) 1 to 3 Shrublands & thickets of exotic species on previously disturbed areas Shrubland-thicket-young secondary forest mosaic Macaranga secondary forest to 12m 2.2 1.7 0 -1.7 5.6 3.4 0 -3.4 0.4 0.4 0 -0.4 Advanced Macaranga secondary forest to 18m (with future potential to developiinto evergreen closed forest ) Advanced mixed secondary forests 16.3 15.5 0 -15.5 (of potential future ECF) 28.2 15.3 0 -15.3 (of potential future ECF) 4 5 6 7 (with future potential to develop into evergreen closed forest ) 8 Deciduous & semi-deciduous vine thickets 0.2 0.1 21.0 + 19.8 9 Semi-deciduous mesophyll vine forests 17.8 14.3 228.1 + 213.8 10 Evergreen closed forests 302.5 197.3 0 -197.3 11 Plantations of trees and shrubs 1.1 1.1 0 -1.1 12 Roads and bare clearings 8.9 1.1 (roads & tracks) 250.2 1.1 (roads & tracks) 250.2 0 TOTAL 383.2 Page 54 of 76 July 2020 Christmas Island vegetation surveys Table 19: Crude estimates of soil/overburden resource remaining for rehabilitation after mining. Note that these estimates provided by the company’s geologist are based on: 1. The actual area that is proposed to be mined after all non-mineable areas (e.g steep terrain and unsuitable lithology in MCI 70/11 and 70/12) and MCI 70/9 are excluded, but not accounting for the minimum 17 to 20 ha of exclusion areas and buffers that will be associated with conservation, heritage and aesthetic features; 2. The estimated volume of resource in each selected area from historical (and often widely spaced) drilling data, or inferred from the nature of the resource in adjacent existing leases; and, 3. The estimated proportion of soil that would not be utilised as a phosphate resource, based on the experience of mining personnel and the likely grade of phosphate in the mined area. Lease MCI MCI MCI MCI MCI MCI MCI MCI MCI 70/ 8 70/ 9 70/ 10 70/ 11 70/ 12 70/ 13 70/ 14 70/ 15 70/ 16 TOTAL Potentially mineable area 1 Estimate total resource volume in mineable areas2 (ha) (wet tonnes) 106.9 0 64.1 9.8 10.1 7.4 52.2 13.9 5.7 1259000 0 1504213 38230.77 98804.35 92000 56000 171000 104839.3 270.1 Estimated % of uneconomic overburden in resource3 Estimated total volume of overburden 10 25 15 5 5 5 25 5 15 125,900 0 225,632 1,911 4,940 4,600 14,000 8,550 15,725 (wet tonnes) 401,260 Page 55 of 76 July 2020 Christmas Island vegetation surveys Table 20: Evergreen closed forest as habitat for threatened and endemic flora of Christmas Island. Species found in the areas selected for possible future mining during the flora survey are indicated by ‘bolding’. *H&H refers to recommended conservation status in report by Holmes & Holmes (2002). Occurrence Restricted to, or mostly found in, evergreen closed forest (ECF) Current EPBClisted species * H&H Endangered or Vulnerable * H&H Poorly- know n * H&H Rare Endemics 2 1 4 10 3 Tectaria devexa var minor Blumea lanceolaria Didymoplexis pallens Peperomia laevifolia Peperomia rossi Zeuxine exilis Amaracarpus pubescens Bryobium pubescens Peperomia rossi Phreatia listeri Zeuxine exilis EPBC --Endangered Pneumatopteris truncata* EPBC --Endangered (* only in a specific & highly localized closed forest type on lower terraces that is associated with seepage areas on exposed basalts) Present in a range of vegetation including ECF 0 Huperzia phlegmaria Leptochilus decurrens Phreatia listeri Pteridrys syrmatica Taeniophyllum hasseltii Tectaria devexa v minor Tectaria dissecta Thelasis capitata 0 0 4 5 Balanophora abbreviata Arenga listeri Brachypeza archytas Flickingeria nativitatis Hoya aldrichii Pandanus elatus Flickingeria nativitatis Strongylodon lucidus Thrixspermum carinatifolia Absent from evergreen closed forest 2 7 7 20 10 TOTAL # OF SPECI ES 4 8 11 33 18 Page 56 of 76 July 2020 Christmas Island vegetation surveys Fig. 1. Location map. Page 57 of 76 July 2020 Christmas Island vegetation surveys Fig. 2. Vegetation of Christmas Island based on forest classification and preliminary mapping of Mitchell (1985). Note that this map was derived largely by correlating gross vegetation categories to the underlying geology. Page 58 of 76 July 2020 Christmas Island vegetation surveys Fig. 3. Existing mine leases & areas selected for possible future mining in relation to the National Park, Christmas Island. Page 59 of 76 July 2020 Christmas Island vegetation surveys Fig. 4. Locations of strategic vegetation transects and detailed survey plots in areas selected for possible future mining in the north-eastern part of the Island (MCI 70/10 to MCI 70/13). Note that transects for each area shown in black are labelled alphabetically (e.g. 10A); plots are shown in red and labelled numerically (e.g. 10.1 etc). Transects are 10m in width. Page 60 of 76 July 2020 Christmas Island vegetation surveys MCI 70/ 9 MCI 70/ 14 Fig. 5. Locations of strategic vegetation transects and detailed survey plots in areas seleted for possible future mining in the central eastern part of the Island (MCI 70/9 & MCI 70/14). Note that transects for each area shown in black are labelled alphabetically (e.g. 10A); plots are shown in red and labelled numerically (e.g. 10.1 etc). Transects are 10m in width. Page 61 of 76 July 2020 Christmas Island vegetation surveys Fig. 6. Locations of strategic vegetation transects and detailed survey plots in areas selected for possible future mining in the south-eastern part of the Island (MCI 70/8, MCI 70/15 & MCI 70/16). Note that transects for each area shown in black are labelled alphabetically (e.g. 10A); plots are shown in red and labelled numerically (e.g. 10.1 etc). Transects are 10m in width. Page 62 of 76 July 2020 Christmas Island vegetation surveys Fig. 7. Location of blocks of vegetation intensively surveyed in the areas selected for possible future mining in the northeastern part of the Island for the presence of threatened plant species. The blocks are classified by habitat type and focus species as follows: A. Limestone cliffs & exposed outcrops for Asplenium listeri & Dendrocnide peltata var murrayana (black, A1 to A6) B. DVT and gaps & edges in SDMVF for Carmona retusa, Asystasia alba, Dicliptera maclearii, Muellerargia timorensis, Cycas rumphii & Dendrocnide peltata var murrayana (green, B1 to B8) C. SDMVF for Spondias cytherea (orange, C1) D. Evergreen closed forest for Tectaria devexa var minor, Blumea lanceolaria & other closed forest dependent taxa (red, D1 to D24) Page 63 of 76 July 2020 Christmas Island vegetation surveys Fig. 8. Location of blocks of vegetation intensively surveyed in areas selected for possible future mining in the southeastern part of the Island for the presence of threatened plant species. The blocks are classified by habitat type and focus species as follows: A. Limestone cliffs & exposed outcrops for Asplenium listeri & Dendrocnide peltata var murrayana (black, A1 to A6) B. DVT and gaps & edges in SDMVF for Carmona retusa, Asystasia alba, Dicliptera maclearii, Muellerargia timorensis, Cycas rumphii & Dendrocnide peltata var murrayana (green, B1 to B8) C. SDMVF for Spondias cytherea (orange, C1) D. Evergreen closed forest for Tectaria devexa var minor, Blumea lanceolaria & other closed forest dependent taxa (red, D1 to D24) Page 64 of 76 July 2020 Christmas Island vegetation surveys Fig. 9. Vegetation map of selected area MCI 70/10. Secondary vegetation refers to natural regrowth in areas that have been previously cleared. Primary vegetation is natural vegetation that has not been cleared; the presence of hatching in areas of primary vegetation indicates the extent and intensity of anthropogenic disturbances. Page 65 of 76 July 2020 Christmas Island vegetation surveys Fig. 10. Vegetation map of selected area MCI 70/11. Second ary vegetation refers to natural regrowth in areas that have been previously cleared. Primary vegetation is natural vegetation that has not been cleared; the presence of hatching in areas of primary vegetation indicates the extent and intensity of anthropogenic disturbances. Page 66 of 76 July 2020 Christmas Island vegetation surveys 40 2000 20 1500 (per ha) No stems >5cm DBH 10 1000 500 ge nt s C M VF +e m er VF C M VF SD C M VF +e m er 50 M D VT ge nt s M VF C M VF SD M VF 0 D VT 0 M VF Canopy height (m) 30 140 120 20 -1 80 2 30 (m ha ) 100 Basal area Maximum height of emergent trees (m) 40 60 40 10 20 Vegetation type M VF +e m er ge nt s C C M VF M VF SD M VF VT D ge nt s +e m er C M VF C M VF M VF SD D M VF 0 VT 0 Vegetation type Fig. 11. Trends in major vegetation structural characteristics across different forest types in quantitative measurement plots on areas selected for possible future mining. Boxplots are used to illustrate the distributional characteristics of the data from these sites. The area in the shaded box represents the data that falls between the first and third quartile of the distribution, with the central line in each box being the median value. ‘Whiskers’ on these plots extend to indicate the upper and lower limits of the data distribution. Page 67 of 76 July 2020 Christmas Island vegetation surveys 2000 70 1500 5 to 25cm 25 to 50cm 50 to75cm 75 to 100cm > 100cm 60 1000 50 180 Basal area (m 2 ha-1) Stem density (No. ha-1) 500 200 160 140 120 100 80 40 30 20 60 40 10 20 0 DVT SDMVF MVF CMVF CMVF+emergents Vegetation structural type 0 DVT SDMVF MVF CMVF CMVF+emergents Vegetation structural type Fig. 12. Structural differences between major vegetation types in distribution of (a) stem density and of (b) basal area between 5 stem size class categories (bars). The data are from the quantitative measurement plots in the areas selected for possible future mining and are presented as means ±standard deviations. Page 68 of 76 July 2020 Christmas Island vegetation surveys Deciduous vine thicket ( 4.1) 10 5 Semi-deciduous mesophyll vine forest Deciduous vine thicket ( 5) 20 ( m) Height of vegetation 30 10 Undifferentiated limestone 30 ( m) Height of vegetation Semi-deciduous mesophyll vine forest ( 1.1) 20 10 Semi-deciduous mesophyll vine forest ( 6.2) ( m) Height of vegetation 30 20 10 10 20 Distance ( m) 30 Fig. 13. Profile diagrams of deciduous vine thickets and semi-deciduous mesophyll vine forests in areas selected for possible future mining. Page 69 of 76 July 2020 Christmas Island vegetation surveys Mesophyll vine forest + Ficus ( 5.2) 20 ( m) Height of vegetation 30 10 40 30 ( m) Height of vegetation Complex mesophyll vine forest ( 1.2) Overgrow n drill-line 20 10 Complex mesophyll vine forest ( 3.1) 30 ( m) Height of vegetation 40 20 10 10 20 Distance ( m) 30 Fig. 14. Profile diagrams of mesophyll vine forests and complex mesophyll vine forests in areas selected for possible future mining. Page 70 of 76 July 2020 Christmas Island vegetation surveys 50 Complex mesophyll vine forest w ith limestone outcropping ( 2.3) 30 ( m) Height of vegetation 40 20 10 10 50 20 30 Complex mesophyll vine forest w ith emergents (1.3) 30 ( m) Height of vegetation 40 20 10 10 20 30 Distance ( m) Fig. 15. Profile diagrams of complex mesophyll vine forests in areas selected for possible future mining. Page 71 of 76 July 2020 Christmas Island vegetation surveys Complex mesophyll vine forest w ith very tall emergents ( 7.8) 50 30 ( m) Height of vegetation 40 20 10 10 50 20 30 Complex mesophyll vine forest w ith very tall emergents ( 1.4) 30 ( m) Height of vegetation 40 20 10 10 20 Distance ( m) 30 Fig. 16. Profile diagrams of complex mesophyll vine forests in areas selected for possible future mining. Page 72 of 76 July 2020 Christmas Island vegetation surveys TREE SPECI ES Deciduous vine thicket Semi- deciduous mesophyll vine forest Mesophyll vine forest ± Ficus Complex mesophyll vine forest Complex mesophyll vine forest w ith emergents Hernandia ovigera Ehretia javanica Cryptocarya nitens Pisonia umbellifera Barringtonia racemosa Syzygium nervosum I nocarpus fagifer Planchonella nitida Tristiropsis acutangula Ficus microcarpa Celtis timorensis Terminalia catappa Guettarda speciosa Acronychia trifoliata Ochrosia ackeringae Pongamia pinnata Kleinhovia hospita Gyrocarpus americanus Melia azedarach Colubrina pedunculata Grewia insularis Grew ia glabra Fig. 17. Range of occurrence of some major tree species across and within the gradient of natural vegetation structura types on Christmas Island. Note that this is qualitative data based on species presence and absence in plots and on transects and does not imply that these species are equally abundant across the range of vegetation types in which they occur. l Page 73 of 76 July 2020 Christmas Island vegetation surveys (a) Evergreen closed forest plots (CMVF + MVF) 60 50 No. species 40 30 Trees, shrubs, vines Ground stratum Epiphytes TOTAL (all species) 20 10 4 .1 10 .2 10 .3 12 .2 12 .3 14 .1 14 .2 14 .3 14 .4 14 .5 14 .7 14 .8 14 .1 15 .3 3 10 9. 2 9. 1 9. 9. 6 4 8. 3 8. 8. 8. 2 0 Plot number (b) SDMVF plots 70 60 No. species 50 40 Trees, shrubs, vines Ground stratum Epiphytes TOTAL (all species) 30 20 10 15 .1 .6 14 .3 13 .2 13 .1 13 1 12 . .4 2 11 . 12 1 8. 0 Plot number Fig. 18. Species-area curves from the quantitative survey plot data. The graphs show the total number of species recorded in two forest types with increasing intensity of sampling. Page 74 of 76 July 2020 Christmas Island vegetation surveys Fig. 19. Geographic sectors of Christmas Island used in collating and analysing the Holmes and Holmes (2002) site data for species of conservation significance. Page 75 of 76 July 2020 Christmas Island vegetation surveys (a) Asplenium listeri A.listeri in sheltered microsite on undifferentiated limestone to the east of MCI 70/ 12 Retention of this deciduous vine thicket to west of t his population would provide a good conservation buffer (b) Tectaria devexa var. minor The solitary individual of T.devexa growing on the edge of a drill-line in MCI 70/ 8 Old drill-lines allow more light to reach the forest f loor but are st ill well-sheltered and maint ain high humidit y -- a sit uat ion that may be a preferred habitat of T. devexa Fig. 20. Single populations of each of two EPBC-listed fern species (Asplenium listeri and Tectaria devexa var minor) found in, or near to, areas selected for possible future mining. Page 76 of 76

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