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

Mountain Lion Movement Patterns in Grand Canyon National Park
Eric C. York, (deceased) Grand Canyon National Park, Box 129, Grand Canyon, AZ
86023, USA.
Rolla V. Ward, Grand Canyon National Park, Box 129, Grand Canyon, AZ 86023, USA,
rv_ward@nps.gov
ABSTRACT Grand Canyon National Park received over 4.5 million visitors in 2007.
From March to November between 110,000 and 160,000 cars per month enter the Park.
Backpacker use in the backcountry amounts to between 280,000 and 300,000 nights per
year. Each of these statistics presents Grand Canyon with significant challenges for
mountain lion management. In order to begin to understand how mountain lions and
humans relate in the canyon we analyzed movement data from 8 lions that were fitted
with GPS collars between November 2003 and December 2006. Individual mountain
lions were tracked from 8 to 408 days. Four collared lions died during the study with all
mortality attributed to humans. Of the 8 mountain lions tracked during this study 7
crossed the major paved roads of the Park. While mean number of crossings per hour for
all mountain lions combined was significantly higher for crepuscular and night periods
(12.2) than for daylight hours (2.6), at least 1 mountain lion crossed major roads during
all hours of the day. Home ranges varied from 437 km2 to 480 km 2 for males and 198 to
445 km 2 for females. Of 63 kill sites investigated, elk < 1 year old were the most
common prey item with numerous caches located near the developed area. Although
most of the radio collared cats had some GPS locations less than 1 km from the
developed area of the South Rim, no mountain lions were located directly within the
developed area. Data from the study have been provided to decision makers involved in
on-going transportation and backcountry planning efforts in the Park.
Proceedings of the Ninth Mountain Lion Workshop
157