Research Document - 2009/036
Information Relevant to a Recovery Potential Assessment of Pure Native Westslope Cutthroat Trout, Alberta Population
By Cleator, H., Earle, J., Fitch, L., Humphries, S., Koops, M., Martin, K., Mayhood, D., Petry, S., Pacas, C., Stelfox, J., and Wig, D.
In November 2006, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) designated the Alberta population of Westslope Cutthroat Trout (Oncorhynchus clarkii lewisi) as Threatened because the pure native populationsFootnote 1 had been reduced by almost 80% as a result of overexploitation, habitat degradation and hybridization/competition with introduced non-indigenous trout (COSEWIC 2006). Remaining pure native Westslope Cutthroat Trout persist mainly as severely fragmented, remnant headwater populations. They are now being considered for legal listing under the Species at Risk Act (SARA). In advance of making a listing decision, DFO Science was asked to undertake a Recovery Potential Assessment (RPA); this Research Document supports the RPA. It describes the current state of knowledge of pure native Westslope Cutthroat Trout in Alberta in terms of their biology, ecology, abundance, distribution and trends, habitat requirements and threats. A recovery goal, mitigation measures and alternatives to threats and the potential for allowable harm are presented, as is information relevant to critical habitat and residence. The information contained in the RPA and this document may be used to inform both scientific and socio-economic elements of the listing decision and, if listed, development of recovery documents and for assessing SARA Section 73 permits.
- Date modified: