Statement of Work and Budget FY2005

BPA Project Number:   2001-034-00
BPA Project Title:   Effects of Cougar Predation and Nutrition on Mule Deer Population Declines in the IM Province of the Columbia Basin
Contract Number:   00006184
Contract Title:   Forge Quality & Mule Deer Conditioning
Performance/Budget Period: FY 2005

Technical Contact Name: Lisa Shipley
Technical Contact Title: Associate Professor
Company / Agency Name: Department of Natural Resource Sciences, Washington State University
P.O. Box 646410
Pullman, Washington 99164-6410
Technical Contact Phone: 509-335-9182
Fax: 509-335-7862
Technical Contact email : Shipley@mail.wsu.edu

Technical Contact Name: Robert Wielgus
Technical Contact Title: Associate Professor
Company / Agency Name: Department of Natural Resource Sciences, Washington State University
P.O. Box 646410
Pullman, Washington 99164-6410
Technical Contact Phone: 509-335-2796
Fax: 509-335-7862
Technical Contact email : wielgus@mail.wsu.edu


Contracting Contact Name: Dan Nordquist
Contracting Contact Title: Director
Company / Agency Name: Office of Grant and Research Development, Neill 423
Washington State University
Pullman, Washington 99164-3140
Contracting Contact Phone: 509-335-9661
Contract Contact email: nordquist@wsu.edu

Financial Contact Name: Julie Lusby
Financial Contact Title: Principal Accountant
Company / Agency Name: Sponsored Programs Services
Washington State University
Pullman, Washington 99164-1025
Financial Contact Phone: 509-335-2074/2071
Financial Contact email: julieal@wsu.edu

Construction of the Grand Coulee and Chief Joseph dams has resulted in inundation and loss of 29,125 total habitat units for mule deer and irrigation agriculture in many parts of the Intermountain Province (IM) of the Columbia Basin.  Mule deer in the shrub-steppe are ranked as high priority target species for mitigation and management and are declining in most portions of the IM.  Reasons for the decline are unknown but are likely related to changes in habitat.  Changes in habitat from conversion of rangeland to irrigation agriculture following the construction of dams on the Columbia River may have contributed to mule deer declines by favoring white-tailed deer that are believed to be increasing throughout the basin.

Habitat changes can cause population declines in mule deer both directly and indirectly. Habitat changes can directly affect a deer's ability to acquire nutrients, maintain thermal balance, and escape disturbance and predation.  For, example, recent studies with elk suggest that late summer/early fall forage conditions determine pregnancy rates and calf growth.  Habitat changes can also affect mule deer by favoring their predators or competitors.  For example, previous research by us in the Northeast IM and adjacent Canadian region suggested that the increasing white-tailed deer populations are resulting in increased predation by cougars (apparent competition or alternate prey hypothesis) on mule deer and/or decreased nutrition of mule deer (food competition hypothesis) (Robinson et al, 2002).  The apparent competition hypothesis predicts that as alternate prey (white-tailed deer) densities increase, so do densities of predators, resulting in increased incidental predation on sympatric native prey (mule deer).  The food competition hypothesis predicts that as competitor density increases, so does nutritional deprivation of native animals, resulting in decreased reproductive success of mule deer.

We have completed 3 years of a 5-year research program to test these hypotheses, beginning in Aug 2001. This report presents progress for year 3 of the 5-year program. The project is divided into two separate but cooperating units, the predation component (Part #1) and the nutritional component, (Part #2).

To date we have collared and monitored 31 cougars (20 female and 11 male).  We have documented 13 mortalities; 11 were shot, one died of natural causes, and one female did not recover following her capture.  One collared female is missing, leaving 17 animals on air.  Despite a relatively high mortality rate, cougar densities in the study area are in the high-average range (3.7 cougars/100km2) of past studies, suggesting strong immigration perhaps in response to high prey availability.  Aerial and ground deer surveys show relative prey availability is 72% white-tailed deer and 28% mule deer.  Selection ratios were 1.53 for mule deer and 0.82 for white-tailed deer (a value of 1.0 would denote no selection).  These results are consistent with per capita predation rates previously observed for mule deer in an adjacent area (Robinson et al. 2002) and the apparent competition hypothesis.  The first year of our whitetail reduction experiment will take place in the fall of 2004.  

Research conducted with captive deer and deer from the sagebrush rangelands have thus far allowed us to develop indices for accurately assessing body fat of live, free-ranging mule deer.  We have also found that about half of the mule deer fawns in the shrub-steppe portion of eastern Washington die within their first 1.5 months, and at least half of this was caused by coyote predation. During that time, twins were more likely to die than singletons.   Body condition of does in mid-gestation did not predict fawn size or condition at birth, nor fawn survival over the summer.   However, the longer the fawn survived, the poorer the doe's body condition was the following winter. This year we bred 39 mule deer does that gave birth to 59 fawns.  Twenty-four of these doe/fawn pairs have been given one of 3 summer/fall nutritional treatments.  We monitored movements, survival, diet, pregnancy and nutritional condition of 117 free-ranging mule deer does, and measured habitat quality and quantity. The experiments with captive deer, field studies and data analyses planned for FY 2005 and 2006 will further elucidate the role of late summer and autumn nutrition and habitat in mule deer population growth.