Dr Diana Fisher, Associate Professor, School of Biological Sciences, University of Queensland
- The species surveys undertaken for the EIS appear thorough and competent. The survey team found 60-75% of mammals that are likely to occur in the sites.
- Generally, there are three main causes of species declines and extinctions; over-hunting/harvesting, habitat loss, and interactions with invasive species. The EIS has discussed how this project may exacerbate these impacts and therefore might affect species persistence and larger-scale biodiversity, and suggested mitigation. However, it has not highlighted both the relative magnitude of these impacts and the probability of being able to substantially reduce each impact via the mitigation strategies in the EIS.
- The most concerning aspect of the project impact is mitigation being focused in the lease area, although much of the impact will be outside the lease area. Most of the mitigation ideas are appropriate, but small scale and fragmented rather than holistic. Limiting mitigation to the project site might result in extinction of the black-spotted cuscus in the region, possibly other Critically Endangered species or restricted-range Montane zone species, and degradation of the world-class biodiversity values of intact forest in the region.
Species New to Science
The surveys found 26 new plants, two new mammals (tree mouse species at the Malia Site and Kaugumi swamp forest site), 26 new frogs, five new reptiles, 17 new odonates (dragonflies) and nine new butterflies. There are also several bats possibly new to science, assessed by their calls.
One undescribed plant, one of the new species of tree mouse, one reptile (a forest dragon only recorded at one site) and two dragonflies were only found in the project disturbance area.
The EIS states that impacts on these species are “unlikely” to be serious because their habitat is likely to extend beyond the study area; however, many of these species may be endemic to the Sepik region, so clearing and flooding of this site combined with the expected surrounding habitat loss might affect a large part of the range of some of these species.
The project site is an area of high conservation value for plants.
Special Value of Biodiversity in Mine Site/Region
- The Lowland and Hill Zone habitats in the project area have very high species diversity of mammals. The Hill Zone is especially important for threatened and newly discovered plants, and for threatened mammals.
- In the North Coast Ranges, the eastern Bewani Mountains, especially Mount Menawa is a ‘Biologically Important Area’ for reptiles and frogs. The Critically Endangered mammals the northern glider, tenkile, and Endangered northern water rat occur in this region.
- The upper Sepik was already highlighted by scientists as needing urgent conservation action. The EIS reports of taxonomic experts confirm this, as the region contains ‘more than 1,354 species of vascular plants, 81 mammals, 220 birds, 58 frogs, 41 reptiles, 107 odonates and 359 butterflies (plus potentially 59 more mammals and 195 more birds)’.
- Around two-thirds of mammal species recorded in the EIS surveys are endemic to mainland New Guinea.
- There are several threatened species important to science in and near the study areas. These include Long-beaked echidnas and Bulmer’s fruit bat.
- For bats, particular roosting caves are important for persistence in the region. The Critically Endangered Bulmer’s fruit bat is concentrated in only two known caves in the world, both are in deep sinkholes in montane and hill karst.
- The domed peat forest is also a rare ecosystem in New Guinea and has been very little studied.
Risks to Biodiversity
- The importance of this site as a refuge for species that have been heavily hunted elsewhere is demonstrated by the high density of threatened species in the project area and surrounds. The Critically Endangered Sir David’s long-beaked echidna (possibly present), Critically Endangered blackspotted cuscus (present), Critically Endangered Telefomin cuscus (possibly present), Critically Endangered Bulmer’s fruit bat (possibly present in or near the site), and the Endangered Goodfellow’s tree kangaroo (present) have been effectively hunted out of many other parts of PNG but still persist / may persist in the project area and / or surrounding intact habitat. These species are at a very high risk of being hunted out in this region as well if the project proceeds.
- Increased population density, more people arriving who do not have cultural connections to this area, access to roads, access to firearms and money are very likely to combine to increase hunting in and beyond the project sites.
- The mitigation measures in the EIS for hunting are appropriate measures, however, there is a risk that measures of banning hunting, and carrying out periodic checks of compliance only in the project area by project staff won’t be enough to prevent impacts. Of the three causes of species decline, hunting is likely to have the highest-magnitude impact on the most highly threatened species in this project. The probability of being able to eliminate the impact of hunting on threatened species via mitigation strategies in the EIS is low.
- Over sixteen thousand hectares will be cleared or inundated. Around 70% will be hill forest and 20% lowland forest.
There will be substantially more clearing than this overall, due to resettlement of four villages, and clearing for housing and gardens for an influx of people working on the project, and on subsequent developments. It is likely that forestry will be enabled in the future due to road developments increasing access. Similar developments have resulted in increased clearing in other areas of PNG in the past.
The impact arising from the loss of high-value Montane forest will be ‘medium’ according to the EIS. It states that less than six hectares of montane forest (above 1000m Above Sea Level) will be directly affected next to the open pit. However, the location of resettled villages is not yet determined, so depending on the final location; impacts to Montane forest (where the local stronghold of the Critically Endangered black spotted cuscus is most likely to be) could be greater.
Habitat loss has the greatest effect on species with small ranges (restricted distributions) by overlapping with most of their range or critical parts of their range.
There are a range of mitigations presented in the EIS which are appropriate, however, most of them will have minimal or modest sized effects on the impacts. The most important mitigations for habitat loss in the EIS are to avoid inadvertently draining the swamp forest, not disturbing peat forest, montane forest, the Nena limestone karst areas (including Bulmer’s fruit bat roost if located), or intact forest of the North Coastal Ranges.
- The EIS documents invasive species in disturbed areas only. The species that they give as examples are all serious invaders of small islands in the Pacific, which are vulnerable to such invasions.
- The largest threat that could be transported into the country by fly in fly out workers is chytrid fungus (Batrachochytrium dendrobatidis), which wasn’t mentioned in the EIS. It is not currently in PNG, but is in Australia and could be transported by these workers. This has decimated frog populations around the world, causing many extinctions, and warrants discussion in the EIS. Six percent of the world’s frogs are in PNG; introduction of this disease would be catastrophic for amphibian conservation beyond the Sepik region.
- The EIS suggests mitigation measures such as chemical washing down points to prevent weeds and pathogens. Inspections of materials brought by people arriving from other countries, limiting roads and tracks, and limiting visits to sites where there are endemic frogs would also be appropriate.
- The EIS suggests that the project is in a good position to start a biodiversity offset program that offsets biodiversity losses by strengthening existing protected areas or making new protected areas in the same zones (e.g. the high-biodiversity Montane zone), or both.
- A good offset protocol for this project would involve prior community consultation and consent, and new protected areas that could include complete or periodic hunting closures of high-value intact habitat (plus complete bans on hunting threatened species, and on clearing) in exchange for agreed and equitable benefits to communities such as schools, well-supported clinics, water tanks etc. This could also engage with immigrants to the area, as well as local villages.
Enforcement and Performance Measures
- There are some enforcement actions and performance measures with insufficient detail to assess if they are likely to be effective, especially the plan to relocate species of conservation concern, the aim of developing a management plan for Bulmer’s flying fox if surveys find a colony, and the plan to prohibit bush meat and firearms / bows and arrows for project workers during project activities. The performance measure is ‘regular inspection’ but what will the response to non-compliance be?
- The EIS suggests relocating any threatened species found in the lease area. This plan is not very well developed, and does not say how relocation sites would be chosen. Many studies have shown that relocating wildlife is usually simply killing them, as the habitat where they are placed is either poor, or already at capacity with competing individuals of the same or other species. A better protocol would be to offer displaced individuals of threatened species to a wildlife conservation organisation that works with the IUCN, and is experienced with PNG threatened species husbandry.
- Several performance measures do not explicitly state the threshold that would trigger action, or the response to non-compliance, for example: ‘monitoring of forest condition at road and facility edges’ simply states that this will be conducted annually, and ‘analysis of imagery to monitor habitat cover and condition’ will be conducted biennially.