Proceedings of the Seventh Mountain Lion Workshop

124
ARE PUMAS OPPORTUNISTIC SCAVENGERS?
JIM W. BAUER, University of California-Davis, Wildlife Health Center, Southern California
Puma Project Field Station, P.O. Box 1203, Julian, CA 92036, USA, email:
jwbauer@uia.net
KENNETH A. LOGAN, University of California-Davis, Wildlife Health Center, Southern
California Puma Project Field Station, P.O. Box 1114, Julian, CA 92036, USA, email:
klogan2@mindspring.com
LINDA L. SWEANOR, University of California-Davis, Wildlife Health Center, Southern
California Puma Project Field Station, P.O. Box 1114, Julian, CA 92036, USA, email:
lsweanor@mindspring.com
WALTER M. BOYCE, University of California-Davis, Wildlife Health Center, One Shields
Avenue, Davis, CA 95616, USA, email: wmboyce@ucdavis.edu
Abstract: We examined scavenging on mule deer (Odocoileus hemionus) carcasses by pumas
(Puma concolor) in the Peninsular Ranges of Southern California. Between 23 January 2001
and 21 November 2002, a total of 42 deer carcasses from road kills, depredation permits, and
euthanized deer were used to determine scavenging events. Seventeen of 42 deer carcasses
(40.5%) were scavenged by 7 to 10 different pumas. Two of the scavenging pumas (males) were
previously telemetered, while 4 pumas (3 male, 1 female) were captured and instrumented at the
scavenging site. Telemetered pumas ranged in age from 11 months to 9 years. Deer carcasses
were found and scavenged by pumas within 1 to 14 days, when carcass conditions ranged from
fresh to rotting and maggot infested. Pumas treated scavenged carcasses as they would their own
kills, dragging untethered carcasses to preferred sites and caching, as well as depositing scats and
making scrapes in the area. However, pumas did not always attempt to cache tethered carcasses.
During the course of our fieldwork we also discovered that one telemetered puma was repeatedly
visiting a domestic livestock graveyard and scavenging on surface-discarded horse and cattle
carcasses. While pumas are known to be opportunistic predators, our results would suggest that
they are opportunistic scavengers as well. Due to pumas’ propensity to scavenge, it is likely that
some perceived puma kills may in fact be scavenging events. Frequent monitoring and timely
field investigation of mortality signals detected from telemetered prey species will help
investigators identify those events. Scavenging behavior should be considered when evaluating
or predicting the effects of puma predation on prey species.
PROCEEDINGS OF THE SEVENTH MOUNTAIN LION WORKSHOP