A Demographic and Genetic Analysis of Minimum Viable Population Size to Inform the Population Reference Value for Wolves in Sweden : Final report

• Main Author: Miller, Philip S.
• Format: Report
• Language: English
• Published: IUCN SSC Conservation Planning Specialist Group 2024
• Subjects: Environmental Sciences; Miljövetenskap; Canis lupus
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:naturvardsverket:diva-10982

In May 2022, the Swedish Government commissioned the Swedish Environmental Protection Agency (SEPA) to investigate, based on the best available knowledge and scientific expertise if, and under what circumstances, the population reference value for the wolf (Canis lupus) as defined for favorable conservation status according to the European Union Habitats Directive, could be between 170 and 270 individuals in Sweden as stated in the parliament proposition from 2012 (prop. 2012/13:191). This report details an independent analysis requested by SEPA to inform future decision-making for wolf conservation in Sweden. Based on the distinction between minimum viable population (MVP) and favorable reference population (FRP) value as described in the Habitats Directive guidance documentation, the analyses described in this report specifically address the identification of a minimum viable population size for wolves in Sweden. Translation of this MVP value to a population abundance incorporating larger-scale ecosystem functionality, representation evolutionary genetic considerations – the FRP value – requires a process of “upscaling†to a larger population abundance. The translational process is outside the scope of this analysis and is instead to be conducted by SEPA after receipt of this PVA. Another important issue governing the interpretation of this PVA concerns the ambiguity around the explicit definition of population viability in the Habitats Directive and supporting documents. To be fully operational, a definition of viability for a specific population should be quantitative and reflect an acceptable level of risk tolerance over a defined time frame. Because this quantitative definition was provided by neither the EU nor SEPA, it is not possible to provide a definitive interpretation of the PVA results in terms of what combinations of characteristics constitute a viable wolf population in Sweden. The process of setting quantitative thresholds for acceptable risk is a complex normative process that must be ...