Yoho National Park of Canada

Wolverine Research Update 2004

Wolverines are rare, occur at low density, and move widely within very large home ranges. Because of this, it's extremely challenging to gather information on their biology, distribution and abundance. Yet, park managers require this science-based information to guide and evaluate management actions. Some means of estimating population size over time is vital to this end. Consequently a wolverine research and monitoring program was initiated in Yoho and Banff National Parks in the winter of 2001-02.

Three winters of fieldwork to detect and monitor wolverine activity have been completed in the 1000 km ² study area. In the first two seasons, snow tracking was used to detect wolverine presence and to collect data on their use of the landscape. Analysis of this information allowed identification of important movement routes through the rugged landscape, also host to major transportation corridors and trails for people. Potential maternal denning habitat was identified and mapped. Trail counters were set up to monitor volume and type of human use on winter trails.

Overall, the presence of wolverine was confirmed, along with the fact that they occur at a low density in the study area. Human use of winter trails was generally high and predictable. It was highest on easily accessible trails, and increased on all trails over weekends. Above a certain threshold of trail users, wolverine presence was not detected. This suggests that one of the factors that influence their distribution and abundance may be human use on the landscape. Some trails will continue to be monitored for trends.

The third field season tested the use of two other monitoring techniques: hair and camera traps. Hair traps are single trees wrapped in barbed wire with an attached scented lure. The barbs snag hairs from animals that climb the tree to investigate the lure. Hairs thus collected are sent for genetic analysis. DNA from one hair follicle allows identification not only to species, but serves as a genetic fingerprint for that individual within the species. Over time with sufficient samples, this information allows an estimate of population size, dispersal distances, and distribution.

To evaluate the effectiveness of hair trap stations, cameras are used in association with them. A camera trap was tested at one of the 21 hair trap stations. Animals climbing the tree break an infrared beam that triggers the camera to take a picture. This captured image verifies if the hair trap actually snagged hair from the animal so detected. This comparison can provide a correction factor for the hair traps, which can be used more widely as an inexpensive monitoring tool.

Though wolverine tracks showed that an animal had passed within two hundred metres of two hair trap stations, hair was not collected at any of the traps. Nor did the camera trap capture an image. It appears that the scented lures were not a sufficient attractant for wolverines to investigate. However, hair traps used in research projects outside parks that used bait (i.e., meat) have proven effective.

Wolverines will continue to be monitored in Yoho and Banff National Parks. Given the low density and wide ranging habit of the animal, park biologists will undertake large scale monitoring in cooperation with Alberta Sustainable Resource Development and the Alberta Research Council, beginning in winter 2004-2005. Track and animal sightings reported by park visitors are a valuable supplement to this effort. A much larger study area will allow monitoring to be responsive to conservation objectives not only at the scale of Banff and Yoho parks, but at a landscape level scale more appropriate to the nature of wolverines and their habitat.