Recipient Organization
UNIVERSITY OF WASHINGTON
4333 BROOKLYN AVE NE
SEATTLE,WA 98195
Performing Department
Wildlife Science
Non Technical Summary
Much research has been done concerning the impacts of gray wolves on ungulates in North America. However, most of this research has taken place in protected areas such as national parks or remote and isolated wilderness areas including the Alaskan interior. Although these past studies have provided much insight regarding wolf-prey interactions, they may not apply to many locations in the continental USA where gray wolves are found or are currently re-colonizing. For example, the state of Washington, and most the western USA, is comprised largely of heavily managed landscapes where anthropogenic modifications include logging, livestock ranching, and game hunting. Such landscapes are continually utilized for their natural resources and host higher numbers of people than most areas where wolves have been previously studied. It is important to understand how wolves impact prey species in heavily managed landscapes for the purpose of implementing proper management decisions that allow for shared use of a resource by big game hunters, subsistence hunters (e.g., native American tribal members), and large carnivores. Furthermore, previous work has primarily focused on how wolves impact one prey species (e.g., elk). Our work, on the other hand, seeks to understand how wolves impact multiple ungulate species within the framework of a managed landscape.The goal of the project is to understand how recolonizing gray wolves might impact mule and white-tailed deer via non-consumptive (i.e., predation-risk causing shifts in habitat use, foraging behavior, herding, etc.) and consumptive (i.e., direct killing of deer causing changes in adult or fawn survival, population growth, etc.) effects. We also plan to investigate how wolves can potentially influence range conditions by impacting either deer behavior, abundance, or both, in effect potentially reducing deer herbivory and impacting range biomass and plant composition. Furthermore, wolves in our study areas are already radio-collared, and WDFW and the Colville Tribe have plans to radio-collar more packs and members within already radio-collared packs. Thus, there is great scope for research into wolf habitat use, food requirements, and overall behavior within a managed landscape.
Animal Health Component
(N/A)
Research Effort Categories
Basic
100%
Applied
(N/A)
Developmental
(N/A)
Goals / Objectives
The goal of the project is to understand how recolonizing gray wolves might impact mule and white-tailed deer via non-consumptive (i.e., predation-risk causing shifts in habitat use, foraging behavior, herding, etc.) and consumptive (i.e., direct killing of deer causing changes in adult or fawn survival, population growth, etc.) effects. We also plan to investigate how wolves can potentially influence range conditions by impacting either deer behavior, abundance, or both, in effect potentially reducing deer herbivory and impacting range biomass and plant composition. Furthermore, wolves in our study areas are already radio-collared, and WDFW and the Colville Tribe have plans to radio-collar more packs and members within already radio-collared packs. Thus, there is great scope for research into wolf habitat use, food requirements, and overall behavior within a managed landscape.With respect to non-consumptive effects of wolves on deer, we will attempt to quantify habitat use, foraging behavior, and anti-predator behavior (e.g., vigilance) of both mule and white-tailed deer in areas with and without gray wolves. We also seek to determine the nature of predation-risk as perceived by each deer species. For example, we will ask whether deer responses to wolf predation risk occur only at times when wolves are nearby, or if deer exposed to wolf predation risk (i.e., within wolf pack territories) regularly exhibit some facet of behavior in an attempt to reduce the danger of being eaten? Furthermore, we will seek to determine if prey behavior, with respect to predation risk, changes with the seasons as abundance of food changes.With respect to consumptive effects of wolves on deer, we will attempt to quantify adult and fawn survival on an annual basis to determine if different age classes of prey are more vulnerable to predation at different times of the year. In addition, we anticipate quantifying abundance of each deer species on a seasonal basis to determine whether or not changes in population growth are occurring and if those changes correlate with fawn survival and recruitment. Furthermore, we will quantify relative abundance of ungulate prey across the landscape (which includes elk, moose, cattle, and wild horses) to determine if wolf prey selection varies seasonally and if wolf packs focus on one or more prey species based on relative abundance of the various ungulate species present on the landscape.Concerning the potential cascading effects of wolves on range conditions, we seek to quantify deer herbivory in various habitat types and see if herbivory changes either due to changes in non-consumptive or consumptive effects of wolves on deer.Lastly, we seek to increase the knowledge of state and federal agencies, and children and adults currently living in Okanogan and Ferry counties where our study will take place, concerning wolves and their impacts on local large ungulate populations.
Project Methods
1. Our first overall goal is to provide detailed information about changes to mule and white-tailed deer foraging, herding, vigilance, and habitat use in response to risk from wolves during winter months. Our specific methods are:a. Gather ~5,040 hours of video footage from GPS camera collars on mule and white-tailed deer (2,520/species). GPS camera collars will record six hours of video/day for two weeks. Sixty deer will be captured during the grant period, and a total of 240 deer will be captured and radio-collared during the lifetime of the project. Footage from the cameras will allow for detailed analysis of foraging behavior (you can see the exact plant species the focal deer is eating), herding (can count number of conspecifics in video), and vigilance (can tell if animal has head up and is scanning for predators).b. Gather ~1,814,400 GPS locations from mule and white-tailed deer (907,200/species). GPS camera collars will take GPS locations every 10 seconds when the camera is recording. This intense level of sampling will provide detailed habitat use data for both deer species during winter months.c. Gather ~1,000 GPS locations from wolves, with GPS collars taking locations every 5 hours. Wolf GPS locations will be taken concurrent to deer GPS locations and will allow for determination of the nature of predation risk (whether deer exhibit anti-predator behavior only when wolves are nearby or they exhibit anti-predator behavior consistently).d. Compare video and location data for deer in areas with and without wolves to determine if wolves influence deer behavior.2. Our second overall goal is to provide detailed pregnancy rates and body condition estimates for radio-collared deer. Our specific methods are:a. Use ultra-sound to determine pregnancy rates in captured does.b. Use ultra-sound to determine rump fat thickness in all deer captured; rump fat thickness gives an indication of body condition.3. Our third major goal is to provide information on adult deer and fawn survival, population estimates, and sex ratios. Our specific objectives are:a. To erect 4 4x4 camera grids for a total of 64 game cameras located across the study area to conduct capture-mark-recapture analyses. Deer captured will be ear-tagged, allowing for 'recapture' in game cameras. From recaptures we can determine population abundance, sex ratios, and survival of adult deer and fawns.b. To compare estimates in areas with and withouts wolves to determine if there is a correlation between wolf presence and deer abundance, survival, and sex ratios.4. Our fourth major goal is to provide information on wolf habitat use and prey selection. Our specific methods are:a. Gather ~1,000 GPS locations from wolves, with GPS collars taking locations every 5 hours. This will allow for a detailed understanding of wolf habitat use.b. Investigate kill sites determined from GPS location clusters to determine prey species killed.c. Determine wolf prey selection patterns based on relative abundance of prey species (quantified using game cameras).5. Our fifth major goal is to provide information on ungulate herbivory across the study area. Our specific methods are:a. Erect 160 5mx5m exlosures in various habitat types within the study area. Exclosures will exclude ungulates only and still allow birds and rodents to forage naturally. [Exclosure plots will be immediately adjacent to control plots]b. Monitor control plots using game cameras to determine which ungulates are foraging where and how intensively.c. Assess plant features in exclosure plots to determine sapling height, density, plant composition, etc.d. Compare exclosure and control plots in areas with and without wolves to detect any indirect effects of wolf predation on plant species.6. Our sixth major goal is to provide project presentations about the wolf-deer research detailed above. Our specific methods are:a. Four presentations will be given to middle and high school science students in Okanogan and Ferry counties.b. Three presentations will be given to town hall meetings in Okanogan and Ferry counties.c. Three presentations will be given at tribal council meetings on the Colville Indian Reservation.