Decision support framework for the conservation translocation of SARA-listed freshwater fishes and mussels

Abstract

For freshwater fishes and mussels listed under the Species at Risk Act (SARA), a federal recovery strategy or management plan identifies recovery measures for best achieving population and distribution objectives. Recovery strategies and management plans for SARA listed freshwater fish and mussel species often identify conservation translocation, specifically supplementation or reintroduction, as a potential approach for improving survival and/or recovery. However, there has been limited progress in undertaking conservation translocations primarily due to basic information gaps on species ecology and uncertainty about how to assess the potential ecological benefits and risks to freshwater species and ecosystems. The objectives of this research document were to: 1) identify and evaluate the potential benefits and risks of conservation translocation as a tool for improving the survival, recovery, or management of SARA-listed freshwater fish and mussel species; and, 2) identify science-based considerations and methods for determining when conservation translocation would be expected to improve the survival, recovery, or management of SARA-listed freshwater fishes and mussels. Benefits and risks of conservation translocations to the focal species and broader ecosystem components are presented, including a decision support framework for evaluating the potential benefits and risks of conservation translocation for SARA-listed freshwater fishes and mussels. The decision support framework consists of five steps: 1) Identify fundamental and means objectives for conservation translocations; 2) Assess the probability of achieving the fundamental and means objectives; 3) Identify and assess the likelihood and magnitude of unintended consequences; 4) Compile and weigh the scientific evidence to inform the translocation decision; and, 5) Implement and monitor the conservation translocation. Using the decision support framework can help determine if and when the ecological benefits of conservation translocations outweigh the uncertainties and ecological risks when attempting to improve the survival and recovery of SARA-listed freshwater fishes and mussels. Future refinement of the decision support framework would benefit from several case studies in addition to those presented in the appendices.