Proceedings of the Ninth Mountain Lion Workshop - Carnivore ...

Cougar Scavenging Behavior and Susceptibility to Snaring at Bait
Stations
Aliah Adams Knopff, Department of Biological Sciences, University of Alberta,
Edmonton, AB T6G 2E9, Canada aliah_ak@hotmail.com
Kyle H. Knopff, Department of Biological Sciences, University of Alberta, Edmonton,
AB T6G 2E9, Canada kknopff@ualberta.ca
Mark S. Boyce, Department of Biological Sciences, University of Alberta, Edmonton,
AB T6G 2E9, Canada
ABSTRACT In western Canada, snares placed around carrion bait are commonly used to
harvest wolves (Canis lupus). Snaring can be an indiscriminant harvest method that can
include by-catch of several species, including cougar. Cougar are known to scavenge,
but the degree to which it makes cougar susceptible to by-catch at bait stations has not
been assessed. We present detailed information on cougar scavenging behavior and
susceptibility to snaring at a study site in west-central Alberta. We monitored 32 cougar
over 3 field seasons (2005-2008) using a combination of GPS and VHF radiocollars.
During this period we visited 2,687 clusters of GPS locations for GPS radiocollared
cougar and we snowtracked collared and uncollared cougar to locate predation or
scavenging events. Scavenging events were recorded only if there was evidence at the
site indicating that the monitored cougar did not kill the animal it consumed. We
documented at least 53 scavenging events by 23 different cougar. Cougar of all age-sex
classes participated in scavenging (47% of cougar scavenged at least once during
monitoring). Twenty-nine cougar were monitored intensively with GPS radiotelemetry
for continuous periods (29 – 649 days) which allowed us to estimate a scavenging rate for
individual animals. Frequency of scavenging was highest for sub-adults (1.38
scavenging events/month) followed by females (0.83/month), and adult males
(0.16/month). Scavenging rates for all cougar in winter (1.29 scavenging events/month)
were more than 4 times higher than in summer (0.30 scavenging events/month).
Seasonal variation in scavenging might be partially explained by carcasses being more
readily available during winter at trapping bait stations and hunter-killed ungulate dump
sites. Six monitored cougar visited and scavenged from bait stations. Two cougar (1
adult male and 1 adult female) were snared and killed, accounting for 25% of the humancaused
mortality of radiocollared cougar during this study. Accidental snaring of cougar
must be reported in Alberta and provincial records show that from January 2000 through
March 2006, 11% of reported human-caused cougar mortality in our study area was the
result of snaring. Our results indicate cougar, especially sub-adults, have a propensity to
scavenge and that this behavior makes cougar susceptible to snares. Management plans
for cougar in areas where snaring of wolves occurs should account for cougar mortality in
snares.
Proceedings of the Ninth Mountain Lion Workshop
156