Fishers in the Biosphere

 Fisher by Julie Dewilde

Fisher by Julie Dewilde

The fisher is possibly the swiftest and most agile member of the weasel family. These elusive creatures are primarily nocturnal but may be spotted during the day. Fishers are agile tree climbing carnivores but spend most of their time on the ground, and are one of the main predators to porcupines.

Fishers were locally extirpated from the Cooking Lake Moraine (aka Beaverhills Biosphere) in the 1940’s due to overhunting and habitat loss. Overall, fishers disappeared in 40% of their historic range which prompted the need for conservation efforts for the species and eventually led to reintroduction attempts. Fishers from Manitoba and Ontario were released in the Cooking Lake Moraine in the early 1990’s.

A recent study, part of the Moraine Mesocarnivore Project, lead by Francis Stewart with the University of Victoria, examined whether today’s population of fishers in the Beaver Hills Biosphere was indeed the outcome of successful reintroductions or if our local fishers actually resulted from recolonization from other Albertan fisher populations.

 Hicks natural area by Alex Nagy

Hicks natural area by Alex Nagy

Cameras and baited hair traps were set up throughout the Cooking Lake Moraine to collect DNA samples from local fishers. The Hicks natural area, co-owned by the Edmonton and Area Land Trust and Nature Conservancy of Canada, was one of the many study sites. The DNA was compared to that of four potential source populations, including fishers in Ontario, Manitoba, and two adjacent populations in Alberta.

The results of the study suggest that our local fishers are more closely related to the nearby Alberta populations than the two populations in Ontario and Manitoba. This means that Alberta fishers recolonized the Cooking Lake Moraine and that the reintroduction efforts were not as successful as they first appeared.

The discussion in the scientific paper - Distinguishing reintroduction from recolonization with genetic testing - outlines a variety of factors that likely contributed to the failure of the reintroduction attempts. The results of this study illustrate how important landscape connectivity and natural area conservation is for maintaining biodiversity and protecting our species at risk.

EALT’s conservation priorities include conserving corridors that are crucial for connecting our increasingly fragmented habitat in the Edmonton region. You can help us conserve important wildlife corridors and habitat by supporting the Edmonton and Area Land Trust through donations and/or volunteering