Review: Abandoned mines as a resource or liability for wildlife

Abandoned Mine Lands (AMLs) are areas where previous mineral extraction or processing has occurred. Hundreds of thousands of AMLs exist within the United States. Contaminated runoff from AMLs can negatively affect the physiology and ecology of surrounding terrestrial and aquatic habitats and species and can be detrimental to human health. As a response, several U.S. federal and state agencies have launched programs to assess health risks associated with AMLs. In some cases, however, AMLs may be beneficial to specific wildlife taxa. There is a relative paucity of studies investigating the physiological and ecological impacts of AMLs on wildlife. We conducted a systematic review examining published scientific articles that assessed the negative and positive impacts of AMLs across invertebrate and vertebrate taxa. We also offer suggestions on evaluating AMLs to develop effective mitigation strategies that reduce their negative tole on human and wildlife communities. Peer-reviewed publications were screened across WebofScience, PubMed and Google Scholar databases. Abandoned mine lands were generally detrimental to wildlife, with adverse effects ranging from bioaccumulation of heavy metals to decreased ecological fitness. Conversely, AMLs were an overall benefit to imperiled bat populations and could serve as tools for conservation. Studies were unevenly distributed across different wildlife taxa groups, echoing the necessity for additional taxonomically diverse research. We suggest that standardized wildlife survey methods be used to assess how different species utilize AMLs. Federal and state agencies can use these surveys to establish effective remediation plans for individual AML sites and minimize the risks to both wildlife and humans.

The Bighorn Habitat Assessment Tool: A Method to Quantify Conservation Value on Landscapes Impacted by Mining

We present a methodology to assess the conservation value of mitigation lands for desert bighorn sheep (Ovis canadensis nelsoni) within landscapes impacted by historic and ongoing industrial uses. The Bighorn Habitat Assessment Tool (BHAT) was developed to support the adaptive management of the Cushenbury population of bighorn sheep located on the north slope of the San Bernardino Mountains in southern California, USA. We use a novel formulation of conservation value integrating the results of resource selection function analysis and reclamation credits, reflecting the degree to which degraded habitat is enhanced to benefit wild sheep. Our method seeks to balance conservation objectives simultaneously with the economic development of a working mine landscape. Specifically, the BHAT can be used to (a) establish a habitat reserve providing maximum benefit to the unique requirements of bighorn sheep; (b) incentivize voluntary action by industry to ensure mining activities are compatible with conservation; (c) allow for the evaluation of multiple mine planning and resource management alternatives; and (d) ensure that future compensatory mitigation actions for mining activity are grounded in the best available science. Our methodology is transferrable to the management of other wild sheep populations occupying mine-influenced landscapes for which sufficient data are available to complete resource selection analyses.