Office of the Environmental Protection Authority A review of subterranean fauna assessment in Western Australia DISCUSSION PAPER February 2012 A review of subterranean fauna assessment in Western Australia Acknowledgment: Cover photo Paradraculoides bythius courtesy of the WA Museum. Recommended citation: EPA (2012) A review of subterranean fauna assessment in Western Australia. Environmental Protection Authority, Perth. 2 A review of subterranean fauna assessment in Western Australia EPA Chairman’s foreword The Environmental Protection Authority (EPA) has legislative responsibility to protect the environment and to prevent, control and abate pollution and environmental harm. It fulfils these duties in part by conducting environmental impact assessment (EIA) of major projects and providing advice to Government on whether the environmental risks and impacts can be managed. While the EPA has been conducting assessments for four decades, it is only in the last 17 years that subterranean fauna has become prominent as a key environmental factor in around 40 major project assessments. Questions have been raised about: • the legal and policy drivers behind EPA consideration of subterranean fauna; • the changing state of knowledge of subterranean fauna in WA; • what has been learned through EIA practice since subterranean fauna was first identified as an environmental factor; • the effectiveness of current assessment practices in meeting the EPA’s objectives; • opportunities to move towards a risk-based approach in considering subterranean fauna; and • potential alternative assessment procedures. In 2011, the EPA resolved to pursue a more risk-based approach to environmental impact assessment of subterranean fauna related issues. The need for and possible approaches to such a change are laid out in this discussion paper. Stakeholder feedback on this discussion paper is invited and will assist the EPA when producing an Environmental Assessment Guideline, which will provide advice to proponents on future requirements for environmental assessment of subterranean fauna. Comments on the following questions are particularly sought, however comments are welcomed on any part of the discussion paper: 1. Your views of the current assessment procedures and what aspects could be changed. 2. The EIA review (EPA 2009a) stated that a risk-based approach to assessment requires the establishment of a systematic, consistent and transparent way of identifying key environmental issues and determining the scale and acceptability of impact. What is your view on applying a risk-based approach? 3. What is your view on using habitat mapping and analysis of gene flow as a surrogate to demonstrate landscape connectivity? This would represent a risk-based approach and an alternative to additional sampling for species found in low numbers. 4. A strategic approach could use regions or geology to predict the likelihood of finding subterranean fauna. This is consistent with the approach used for short range endemic invertebrates (Guidance Statement 20) and current procedures for terrestrial vertebrate fauna. Regional context, type of impacts and existing site knowledge about subterranean fauna could then be used to determine the information required for assessment. In your view, is this a valid approach for subterranean fauna assessment? Your comments to [email protected] would be appreciated by 30 March 2012. 3 Dr Paul Vogel A review of subterranean fauna assessment in Western Australia Executive summary Subterranean fauna occur below the surface of the earth and include two groups - stygofauna (aquatic) and troglofauna (air-breathing). Micro-habitats are provided by geology, water and spaces, ranging from small pores to aquifers. Subterranean fauna are known from karst (such as limestones and calcretes) and non-karst (banded iron formations, alluvial deposits and fractured rock aquifers) geologies. Species now occupying subterranean habitats have evolved from the fauna which lived at the surface before the aridification of the Australian continent. There are several ecological characteristics of subterranean fauna; • They are restricted to specific habitat types; • They often display evolutionary adaptations such as reduced pigment and reduced, poorly functioning or non-existent eyes; • They have simple food webs with few trophic links, species are either predators or detritivores; • They are thought to have slow metabolism, be slow-growing and long-lived, and have few young (although the life-histories of WA subterranean fauna are poorly known); and • They often have discontinuous distributions. The challenges faced in understanding the subterranean environment are significant and fauna can defy orthodox understanding of species and genetic diversity. In addition, the nature of the subterranean environment means that fauna may be vulnerable to local impacts if they have limited ranges and poor dispersal abilities. Western Australia has a diverse subterranean fauna, estimated to be over 4000 species including 500 – 550 species thought to occur in Pilbara groundwater alone. Subterranean fauna found at Cape Range and Barrow Island, the Yilgarn and the Pilbara have been recognised as significant (diversity and endemicity of species). The Cape Range area has been inscribed on the World Heritage list for its biodiversity values (including the subterranean fauna). WA is home to forty threatened subterranean fauna species (two fish and 38 invertebrate) and nine threatened subterranean ecological communities. The EPA has released two guidance statements regarding subterranean fauna (dealing with consideration during environmental impact assessment in 2003 and sampling and survey in 2007) which have informed assessment of environmental impacts. Subterranean fauna were first recognised as a key environmental factor in the mid-1990s and subsequently about 40 proposals have included the factor. Since 2000, the Pilbara has become the main focus of subterranean fauna assessment, as a result of the significance of the fauna and number of resource developments. The EPA may recommend conditions for implementation that are designed to increase knowledge and reduce risks to subterranean fauna. The Minister for Environment is responsible for issuing a statement to allow implementation, and in almost all cases, the EPA’s recommendations have been included by the Minister. This discussion paper includes a series of case studies which show the evolution in environmental impact assessment thinking and methodology. Many advances in knowledge of subterranean fauna have been made, particularly in the description of new species, however there are still major gaps in the knowledge of biology, environmental requirements and impacts on subterranean fauna. In addition, the information gained in assessment and post-approval conditions is often not used effectively to improve knowledge of subterranean fauna, although the EPA acknowledges the reasons for this are complex. Despite this, WA’s approach, when compared to other jurisdictions is integrated and consistent in assessment of subterranean fauna. 4 A review of subterranean fauna assessment in Western Australia There are a number of limitations with the EPA’s current approach to assessment of impacts on subterranean fauna. These include: • requirements to advise the Minister regarding the risk of species extinction; • interactions between genetic and morphological variations; • understanding assemblages and distributions when the representativeness of survey is arguable and many species are sampled infrequently; • difficulties with access to the subterranean environment (e.g. requirement for drill holes or bores) and surrounding areas for comparison as part of assessment; • distinguishing environmental impacts from background environmental variability; and • inconsistency between existing guidance for subterranean fauna and other EPA policy (notably that relevant to short range endemic invertebrates). The EPA has identified the need to adopt a more strategic and risk-based approach to the assessment of impacts on subterranean fauna. This discussion paper examines options for future directions in assessment and how this may be applied. The EPA proposes using information on the distribution and population structure of widespread species as surrogates and the extent of relevant habitat to demonstrate landscape and genetic connectivity. Multiple lines of evidence and on-ground survey (although perhaps different from that which is undertaken currently) would be necessary to satisfy the EPA that subterranean species are not restricted to an area impacted by development. The EPA is also considering a strategic approach which could use regions or geology to predict the likelihood of finding subterranean fauna (consistent with the approach for short range endemic invertebrates). Requirements for information during assessment could be based on regional context, type of impacts and existing site knowledge about subterranean fauna, but this would likely result in significant differences across WA. This discussion paper forms the basis for a stakeholder comment process to determine direction and content for a future Environmental Assessment Guideline, which will provide advice to proponents on future EPA requirements (including specific procedures, methodologies, minimum requirements, when a strategic approach would be appropriate and managing uncertainty) where subterranean fauna is a likely to be an environmental factor. 5 A review of subterranean