Current Projects
Effects of trophy hunting and sexually selected infanticide on female cougar population growth and persistence
Dana Morrison, A. Ford, G.M., Koehler, and R.B. Wielgus.
This project is ongoing as part of Dana Morrison’s M.S. thesis. Dana will be calculating the effects of adult male trophy hunting and resulting male immigration on incidental female hunting mortality and kitten infanticide. She will examine the unanticipated effects of sport hunting of males on female cougar population growth and persistence.
Lynx Habitat Selection in North Washington
Ben Maletzke, G.M. Koehler, R.B. Wielgus & others
This project is on-going as part of a collaborative effort by WSU, WDFW, WADNR, UW, USFS, and USFW. Snow tracking studies (Koehler et al. 2008) shows lynx in winter to select for Engelmann spruce and subalpine fir forests with moderate canopy and understory cover (11-39%), with flat to moderate slopes (<30°) and avoid Douglas-fir and ponderosa pine forest, forest openings, and recently burned areas with sparse canopy and understory cover (<10%), low elevations (<915 m), and steep slopes (>30°). It is not known whether lynx select and avoid the same features during snow-free periods, nor whether this model is valid where habitats are dominated by lodgepole pine, as occurs on the landscape remaining on the Loomis State Forest and Okanogan-Wenatchee National Forest. If lynx are to remain a part of the boreal forests ecosystem in Washington, an understanding of their habitat throughout the year and over multiple landscapes is needed. Managers must understand how lynx utilize resources during all season, particularly during snow free seasons when forest management and recreational activities are greatest.
We will test the hypothesis that lynx select Engelmann spruce and subalpine fir forests, moderate canopy and understory cover (11-39%), and flat to moderate slopes (<30°) and focus their activities for foraging in stands with > 0.5 hares/ha (Koehler et al. 2008, Maletzke et al. 2008) throughout the year. In addition, we will test the hypothesis that lynx avoid Douglas-fir and ponderosa pine forest, forest openings, and recently burned areas with sparse canopy and understory cover (<10%), low elevations (<915 m), and steep slopes (>30°) (Koehler 1990, Koehler et al. 2008) during winter and snow-free seasons on the Okanogan-Wenatchee National Forest and Loomis State Forest, where lodgepole pine dominates the landscape and where habitat is highly fragmented by wildfires and timber harvests.
Effects of Hunting on Cougar/Human Conflicts
Ben Maletzke, G.M. Koehler, H.S. Cooley, & R.B. Wielgus
This project is on-going as part of Ben Maletzke’s Ph.D. program. Heavily hunted and white-tailed deer occupied areas appear to show much greater incidences of cougar-human conflicts (cougar complaints, cougar use of human occupied areas; attacks on humans, pets, and livestock) than lightly hunted, white-tail free areas. We hypothesize that heavy hunting of resident adult cougars in such areas results in high rates of immigration and settling by sub-adult males and that these males use human-occupied and white-tailed deer areas, and cause more attacks than adults. Results to-date indicate that unhunted, older, resident cougars have stable home ranges and avoid human-occupied areas whereas hunted, younger, immigrant cougars have unstable home ranges and use human-occupied areas. Heavy hunting and white-tailed deer expansion appears to exacerbate, not alleviate, cougar/human conflicts.
Effects of Hunting on Cougar Prey Selection and Sexual Habitat Segregation
Jon Keehner, H.S. Cooley, and R.B. Wielgus
This project is on-going as part of Jon Keehner’s M.S. to Ph.D. Program. Cougars selectively prey on mule deer but not sympatric white-tailed deer. We tested and rejected the hypothesis that many mule deer killed by cougars are actually mule deer/white-tailed deer hybrids that have poor predator avoidance and escape strategies. We also tested and supported the hypothesis that selection for mule deer was caused by cougar sexual habitat segregation. Only females (especially those with kittens) select for mule deer. Our preliminary results suggest that high mortality of resident adult males and corresponding high immigration by potentially infanticidal males results in sexually selected habitat segregation. Females with vulnerable offspring appear to select for high elevation, low density, mule deer ranges where infanticidal immigrant males are rare. Males select for low elevation, high density white-tailed deer ranges. Hunting of cougars may actually exacerbate, not alleviate, high predation on declining mule deer.
Population Growth and Persistence of Endangered Mountain Caribou in the Selkirk Mountains
Jon Almack, W. Wakkinen, & R.B. Wielgus
This project is on-going as part of a collaborative effort by WSU, WDFW, IDFG, USFS, and USFW.We determined rates and causes of mortality, reproduction, and population growth for the last remaining mountain caribou population in the lower US. Results indicated that this population was decreasing because of high predation by cougars due to expanding white-tailed deer. First year survival of transplant caribou was much lower than in subsequent years. This appears to be due to capture and handling stress, not naive prey hypothesis. Demographic analysis suggests the population is currently stable after cougar reductions and Population Viability Analyses (PVA) suggests the population can recover with additional transplants.
Completed Projects
- Effects of Sex and Age on Cougar Prey Selection in a Mule Deer and Elk Community
- Quantitative Population Ecology of Pyrenees Brown Bears in France and Spain
- Effects of Hunting on Cougar Population Ecology
- Effects of White-tailed Deer on Cougar Predation of Mule Deer: A Test of the Apparent Competition Hypothesis
- Cougar Prey Selection in a Mule Deer & White-tailed Deer Community
- Lynx Habitat Selection in North Washington
- Cougar Population Dynamics in the Northwest
- Effects of Forest Fragmentation on Cougar Predation of Endangered Mountain Caribou
- Minimum Population Size for Grizzly Bears in the North Cascades of WA and BC
- Effects of Forestry on Grizzly Bear Habitat Use
- Cougar Predation and Population Growth of Sympatric Mule Deer and White-Tailed Deer
- Effects of Trophy Hunting on Grizzly Bear Habitat Use, Population Growth, and Persistence
- Effects of Sex and Age on Black Bear Conifer Damage and Control