Date:
February 13, 2015
Source:
University of California - Santa Cruz
Summary:
Female pumas kill more
prey but consume less when their territories bump into human
development, researchers report in a new study based on monitoring more
than two dozen pumas in the Santa Cruz Mountains.
7F, an
approximately 7-year-old mother is treed by trailing hounds in 2013 so
researchers can replace her collar before the batteries fail. 7F lives
in the mountains above Los Gatos, Calif. and has had three litters of
kittens in the four years since she was first collared. Credit: Paul Houghtaling, UC Santa Cruz
Female
pumas kill more prey but consume less when their territories bump into
human development, UC Santa Cruz researchers report in a new study based
on monitoring more than two dozen pumas in the Santa Cruz Mountains.
The presence of humans -- homes, roads, and other development --
means pumas are fearful and stay on the move rather than returning to a
kill site to fully consume prey, the study finds.
"We investigated how higher housing densities influenced puma behavior at kills and how often they killed," said Justine A. Smith, a Ph.D. candidate in the UC Santa Cruz Environmental Studies Department. "We found that female pumas spent less time feeding at kill sites as housing increases."
The effects can impact deer populations as well as puma breeding success, Smith and her coauthors write in the March 7, 2015 issue of the journal Proceedings of the Royal Society B. "Females killed 36 percent more deer per year in developed habitats than in areas with little housing," Smith said. "Increased kill rates may lead carnivores to waste energy and also influence prey survival rates in human-modified landscapes."
"We conclude that food loss and high energy costs due to human avoidance at kill sites is compensated for by increasing kill rates," she said.
Smith, and co-authors Yiwei Wang, a recent UC Santa Cruz Ph.D graduate, and Chris Wilmers, associate professor of environmental studies, are part of the Santa Cruz Puma Project that has studied puma behavior since 2008.
For this study they looked at the actions of 30 animals that had been captured and later released with GPS monitoring collars. The collars record and transmit not only location and travels but also hunting behavior such as bursts of speed or pounces.
The team found that the greatest impact on pumas was when their hunting territories were within 150 meters of human development. They also found that females have a smaller range than males but higher kill rates. Females killed an average 67 deer per year compared with nearly 44 for males whose ranges are approximately three times as large.
"We investigated how higher housing densities influenced puma behavior at kills and how often they killed," said Justine A. Smith, a Ph.D. candidate in the UC Santa Cruz Environmental Studies Department. "We found that female pumas spent less time feeding at kill sites as housing increases."
The effects can impact deer populations as well as puma breeding success, Smith and her coauthors write in the March 7, 2015 issue of the journal Proceedings of the Royal Society B. "Females killed 36 percent more deer per year in developed habitats than in areas with little housing," Smith said. "Increased kill rates may lead carnivores to waste energy and also influence prey survival rates in human-modified landscapes."
"We conclude that food loss and high energy costs due to human avoidance at kill sites is compensated for by increasing kill rates," she said.
Smith, and co-authors Yiwei Wang, a recent UC Santa Cruz Ph.D graduate, and Chris Wilmers, associate professor of environmental studies, are part of the Santa Cruz Puma Project that has studied puma behavior since 2008.
For this study they looked at the actions of 30 animals that had been captured and later released with GPS monitoring collars. The collars record and transmit not only location and travels but also hunting behavior such as bursts of speed or pounces.
The team found that the greatest impact on pumas was when their hunting territories were within 150 meters of human development. They also found that females have a smaller range than males but higher kill rates. Females killed an average 67 deer per year compared with nearly 44 for males whose ranges are approximately three times as large.
Story Source:
The above story is based on materials provided by University of California - Santa Cruz. The original article was written by Guy Lasnier. Note: Materials may be edited for content and length.
The above story is based on materials provided by University of California - Santa Cruz. The original article was written by Guy Lasnier. Note: Materials may be edited for content and length.
Journal Reference:
- J. A. Smith, Y. Wang, C. C. Wilmers. Top carnivores increase their kill rates on prey as a response to human-induced fear. Proceedings of the Royal Society B: Biological Sciences, 2015; 282 (1802): 20142711 DOI: 10.1098/rspb.2014.2711
Cite This Page:
University
of California - Santa Cruz. "Female pumas kill more, eat less when
humans are near." ScienceDaily. ScienceDaily, 13 February 2015.
<www.sciencedaily.com/releases/2015/02/150213145130.htm>.
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