Technical Bulletins & Special Reports

Technical Bulletin No. 1005: A Review of the History and Scientific Basis of Species at Risk Assessments in Canada

The maintenance of biodiversity and the management of its related elements are important aspects of environmental resource management at the international, national, and local scales. When species populations decline to the point that extinction is a potential consequence, stopping and reversing that trend is an imperative. Determining which species are in need of conservation action, which species are in more desperate need, and determining the tools that should be applied, is a complicated affair. Theoretical and practical efforts in the fields of ecology, genetics, and conservation biology have contributed significantly to our ability to assess, prioritize and manage species at risk. Species at risk assessment, which took root in the late 1800s, is undertaken at the global scale by the International Union for the Conservation of Nature (IUCN) through its Red List of Threatened Species IUCN is charged with determining the relative risk of extinction for all species on the planet. Within Canada, species are assessed as to their relative risk of extinction by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), which bases its species risk assessment process on the IUCN process, with some modifications. This report reviews the science of species assessment and application of that science to both the IUCN and COSEWIC processes, and identifies a number of opportunities for strengthening the process in Canada. A more transparent and repeatable assessment process, and more effective incorporation of elements such as natural rarity, temporal and geographical scale, and marginal species dynamics, should serve to increase the reliability and accuracy of the assessment process, thereby increasing the efficiency and effectiveness of species at risk management in Canada.