Ya Ha Tinda Elk ProjectThe Ya Ha Tinda Elk Project is a fourteen year, ongoing research initiative on the elk population of the Ya Ha Tinda (YHT) ecosystem in Alberta. Once one of the largest migratory elk populations in Canada, the YHT herd has experienced significant declines since the mid-1990s. In 2013, SCI Foundation partnered with the University of Alberta, University of Montana, Parks Canada, Alberta Conservation Association, and other local groups to determine the factors behind this observed decrease.
A decline in the elk population has been concurrent with a reduction in the number of elk migrating westward to summer in Banff National Park and an increase in elk remaining on the YHT winter range year-round. During recent years, there has also been a new, eastward migration by a segment of the herd onto industrial forest lands. This change in migratory behavior may be driven by wolf predation or habitat quality.
“Our long-term research continues to monitor shifts in adult elk distribution and demography, but we are now focused on an in-depth calf mortality study” says Jodi Berg, a PhD Candidate at the University of Alberta.
Berg and fellow scientists are studying both radio-collared adult female elk and calves to track migration behavior and cause-specific mortality. One hundred and twelve adult cow elk have been free-range darted and fit with vaginal implant transmitters (VITs) to assist in the capture and tagging of calves. Efforts over the past 3 years have resulted in 83 tagged calves. Understanding factors impacting calf recruitment is critical to the project.
Using site inspection and analyses of DNA from predator saliva left on calf remains, researchers are able to identify locations and sources of calf mortality. Mortality appears to be dominated early on by bears, followed by wolves and cougars. Preliminary results indicate that calf survival is twice as high in the new eastern migrants.
“One of our main objectives is to identify the interaction of habitat factors with predation events to understand their role in spatial shifts in elk distribution. We hypothesize summer calf survival to be the major factor in the observed distributional shifts and decline in the population. Our study addresses whether the new migration of elk to industrial forest lands east of YHT is related to elk density, cow elk selection for improved forage from timber harvest, or reduced calf mortality associated with predator exploitation or human disturbance.” – Jodi Berg
Alternatively, burning and timber harvest may also attract bears, particularly grizzlies, to foraging sites of elk, thus increasing predation on calves. Therefore, calf survival is a key link to the overall understanding of predator-prey dynamics in the YHT system.
The Ya Ha Tinda Elk Project is one of the longest-running studies on elk in an intact ecosystem under wolf and grizzly bear predation in North America. This research will continue to improve understanding of the factors affecting calf recruitment and migratory behavior in the YHT elk population and allow for more effective wildlife management.
Information in this Project Update was provided by the Ya Ha Tinda Elk Project.