Greater Yellowstone Wolverine Program

Authors(s): R. M. Inman, K. H. Inman, R. R. Wigglesworth and J. J. Beecham

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Publication Date: 0000-00-00

Type: 2002 annual report

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Abstract: EXECUTIVE SUMMARY Wolverine ecology in the lower 48 United States is not well documented. Federal and state resource managers need information in order to make well-informed policy decisions that affect land-use practices and populations of wolverines. Wolverines are currently on the U.S. Fish and Wildlife Service list for consideration as a threatened or endangered species. This determination will be a particularly difficult task. This project is designed to provide needed information and answer specific questions relevant to wolverine management and related land-use policies. A successful conservation strategy for wolverines in the Greater Yellowstone Ecosystem (GYE) requires documentation of population demographics and determination of the human and ecosystem influences that affect population dynamics. Two areas, the Madison Range of southwestern Montana and the Teton Range of northwestern Wyoming, have been selected for intensive study. These areas were chosen because they are representative of the land management jurisdictions and human-use impacts that are common to the GYE. Variation in jurisdiction, management policies, and human-use impacts between these two study areas will facilitate our ability to compare and contrast influences on wolverine population dynamics. During this first year of full implementation of the wolverine program, we accomplished many objectives necessary to begin field research. We created a detailed study plan, equipped and organized two field offices, and obtained various permits necessary to conduct the research. We purchased field equipment and created data-forms, field protocols, and databases. We secured funding and in-kind support for the program. We researched and purchased four GPS collars for use on wolverines. We developed kit capture and summer recreational survey methodologies and protocols. Numerous other first-year accomplishments were made. On the Teton Range Study Area (TRSA), we constructed four new wolverine traps. Nine traps were open for a total of 677 trap-nights, during which time five wolverines (3 females and 2 males) were captured nine times. Capture rate for the TRSA was one wolverine capture per 75.2 trap-nights. We fitted a male wolverine with a GPS collar, and retrieved the collar after it had been on the wolverine for approximately one month. This is the first ever GPS collar to be placed on a wolverine to our knowledge. We are awaiting data from the store-on-board collar. We documented the mortality of an adult male wolverine who was killed in an avalanche. We will continue to pursue development of GPS technology for use in the study. We will expand trapping coverage and implement recreational surveys during the upcoming year. We will continue to pursue financial and in-kind support for the program. Full implementation of the study may require additional personnel. ----------------------------------------------------------- WOLVERINE ECOLOGY IN THE NORTHERN ROCKY MOUNTAINS The wolverine (Gulo gulo) is a medium size carnivore that inhabits the most remote areas of the Northern Hemisphere and is arguably one of the least understood carnivores in North America. Wolverine habitat normally encompasses large areas of rugged, remote terrain, and populations naturally exist at relatively sparse densities. In the lower 48 United States, the wolverine's unobtrusive nature and the difficulties associated with studying such an inaccessible and uncommon creature has resulted in a lack of documentation of wolverine status and ecology. This void of available information is hindering state and federal natural resource managers who face a number of difficult decisions. Wolverines are currently on the U.S. Fish and Wildlife Service list for consideration as a threatened or endangered species. This determination will be a particularly difficult task. Even in historically occupied range that has not been subjected to human encroachment, wolverines naturally exist at very low densities. Therefore, an assessment of a "low number" of individuals in the Northern Rockies will not be conclusive evidence of a population in danger of extinction. To ensure adequate protection of wolverine populations and that limited endangered species funding is being used most effectively, careful assessment of wolverine status and viability is required. Many other decisions impact land-use policies, and managers are required by law to consider wolverine ecology and sustainable population management in their decisions. Agencies charged with the sustainable management of wolverine populations on multiple-use lands are currently wrestling with issues such as the impacts of winter recreation on wolverine reproduction, habitat management, sustainable trapping quotas, and methodology for assessing population status and trend. In all cases, the paucity of information regarding wolverine ecology limits the ability of managers to make well-informed, defensible decisions that can advance conservation of this species. The primary goal of this study is to provide managers with the information necessary to make informed decisions. All documentation that this study will provide in regard to population dynamics, denning habitat, and human-use impacts will be relevant to many management decisions. Wolverines are also an important component of the carnivore guild in the Greater Yellowstone Ecosystem (GYE). A comprehensive land management plan for the GYE will benefit from knowledge of the relationship that wolverines have with other carnivore populations, prey species, and ecosystem dynamics. This research effort is designed to be compatible with The Wildlife Conservation Society's Living Landscapes Program. The purpose of the Living Landscapes Program is to utilize landscape, or umbrella, species to 1) define an ecologically meaningful conservation landscape across jurisdictional boundaries, 2) identify locations in time and space where the needs of people and wildlife clash, and 3) define land management strategies that can help people and wildlife share these valued areas (Weber et al. 2001). The wolverine, because of its wide-ranging use of remote habitats, potential susceptibility to disturbance, and relatively vulnerable population demographics, is one of several species being considered for designation as a landscape species. Healthy wolverine populations may indicate overall ecosystem health to a greater degree than most species. Their scavenging habits likely benefit from the consistently high turnover rate of ungulate biomass that would result from healthy ungulate populations and habitats along with intact carnivore assemblages (Van Zyll de Jong 1975, Hornocker and Hash 1981). Thus, management for wolverine persistence is a logical component of a large scale, multi-species conservation effort. PROJECT PERSONNEL The wolverine program falls under Dr. John Beecham's duties as WCS' Western Field Coordinator. Dr. Beecham oversees project development, directs study design, coordinates multi-agency interests, regulates budgets, and reviews reports and publications. Kristine Inman, M.S. and Robert Inman, M.S., are coordinators of the wolverine program and lead the research on the Madison Range Study Area. As coordinators they are responsible for study design, developing data forms and protocols, ensuring consistency in data collection between the two wolverine study areas, and providing guidance to the TRSA. Their duties also include MRSA budget development and monitoring of monthly expenditures; live capture of wolverines, data collection; database management; authoring reports and scientific publications; selecting, training, and directing other field personnel; and representing WCS at meetings and conferences. Rachel Wigglesworth, M.S. leads the research on the Teton Range Study Area. Her duties include developing protocols; budget development and monitoring monthly expenditures; live capture of wolverines, data collection; database management; authoring reports and scientific publications; selecting, training, and directing field personnel on the TRSA; and representing WCS at meetings and conferences. Dr. Kathy Quigley is the veterinarian coordinator for the western field studies and is responsible for providing all aspects of veterinarian oversight, selecting and coordinating other veterinarians who will provide surgical immobilization of radio-implanted animals on the Wolverine Program. Craig and Eli Burr conducted trap building efforts and established, maintained, and checked the TRSA western slope traps. Heath Smith conducted trap building efforts and established, maintained, and checked the MRSA traps. Ted Chu, provided training for trap construction and helped build TRSA traps. PROJECT DURATION Full implementation of the wolverine research project began September 15, 2001 and is targeted as a 5-10 year field effort to document wolverine ecology, determine the impacts of various human activities on wolverines, and assimilate information for use as a component of a large scale, multi-species conservation effort in the Greater Yellowstone Ecosystem. APPROVED BUDGET During fiscal year 2002, the Madison Range Study Area had an approved budget, including all associated salaries, of $125,500; the Teton Range Study Area had an approved budget, including all associated salaries, of $122,500. STUDY AREAS A successful conservation strategy for wolverines in the GYE requires documentation of population demographics and determination of the human and ecosystem influences that affect population dynamics. Two areas, the Madison Range of southwestern Montana and the Teton Range of northwestern Wyoming, have been selected for intensive study (Figure 1). These areas were chosen because they are representative of the land management jurisdictions and human-use impacts that are common to the GYE. Variation in jurisdiction, management policies, and human-use impacts between these two study areas will facilitate our ability to compare and contrast influences on wolverine population dynamics. Teton Range The Teton Range Study Area (TRSA) covers approximately 1,500 square miles (3,885 km?), and is located within several differing land management jurisdictions. The majority of the TRSA is located in Grand Teton National Park (GTNP) and the adjacent Jedediah Smith Wilderness (JSW). As a result, over 427,000 contiguous acres are highly restricted with regard to motorized access. Portions of the TRSA fall within the multiple-use lands of the Caribou-Targhee National Forest and the Bridger-Teton National Forest. Wyoming Highway 22 (Teton Pass) is located at the southern end of the TRSA and may serve as a barrier to wolverine movements. Two ski areas exist in the TRSA, Teton Village on the east slope and Grand Targhee on the west slope. The mountains on the east slope of the Tetons rise steeply from the valley floor, while the west slope is characterized by rolling foothills that lead into the mountains. Wolverines use areas north of the Tetons, which are heavily timbered but are lower elevation and are not in the rugged peaks. Ungulate winter range is primarily the National Elk Refuge, close to the town of Jackson, Wyoming. Winter recreational use in the Tetons is characterized by backcountry skiing on the east slope concentrated in the southern portion of the range and both backcountry skiing and snowmobiling on the west slope. Helicopter skiing occurs in the southern part of the TRSA. Recreational use increases during the summer mainly in the form of day and overnight backcountry travel. The northern portion of the Tetons receives relatively little winter or summer recreational use, especially on the east slope. The northern portion of the study area receives relatively little human use in comparison to the southern portion of the study area. Ungulate hunting occurs primarily on the west slope of the Teton Range. Wolverines are not subject to recreational fur trapping in the TRSA. Grizzly bears and wolves exist within the TRSA, but at relatively low densities. Their populations are likely to continue to expand into the TRSA. ACTIVITIES/PROGRESS Teton Range Study Area Office Related Accomplishments. We equipped and set-up the TRSA field office. We obtained permits from WDGF and USFS to capture wolverines, collect bait for captures, and construct log box-traps. We purchased field equipment and established and recorded field protocols. We made numerous contacts with state and federal agency personnel, interested NGO's, and local businesses. We monitored budgets and completed accounting duties for all study area expenditures. We attended the Western Forest Carnivore Committee Conference in Spokane, WA, a veterinary immobilization course at the Henry Doorley Zoo in Omaha, NE, and the WCS North American Program meeting in Blue Lake, NY. We hired personnel to complete TRSA recreational surveys. A proposal for the necessary permit to build traps within GTNP was written and approved. Financial and in-kind support was secured from the Bridger-Teton National Forest, the Caribou-Targhee National Forest, and the Greater Yellowstone Coordinating Committee. A Memorandum of Understanding was established with the Caribou-Targhee National Forest. Logistical aspects of a new study, including hiring technicians, developing protocols, and purchasing field equipment were completed. A draft protocol for determining the behaviors of reproductive females was developed and tested. A proposal for the necessary permit to capture wolverine kits within GTNP was written and approved. Winter Capture Effort.Two of four approved log box traps were constructed in GTNP, and two additional traps were built on the West slope of the study area, bringing the total number of traps on the TRSA to nine. Nine log box traps were opened in the TRSA between late December 2001 and early January 2002 and were closed in late March 2002 for a total of 677 trap nights. Two of these traps were located in the southern portion of Grand Teton National Park on the east slope, and seven were on the west slope, three of which were operated by the Alta Wyoming 4H Natural Resources Club. We captured five wolverines nine times. All but one of these captures occurred on the east slope. Twenty-one marten, nine red fox, and one coyote (Canis latrans) were incidentally captured (Table 1). One red fox was killed as a result of a trap injury. For the 2001-2002 winter trapping season the number of trap nights to capture one wolverine was 75.2 nights when including wolverine recaptures and was 135.4 nights for initial wolverine capture (Table 1). The two traps located on the east slope, both within Grand Teton National Park, had a higher success rate of not only wolverine captures but also incidental captures than traps located on the West slope. We captured five wolverines, three females and two males during the winter 2001-2002 capture season (Table 2). Three of these wolverines were recaptures from previous years that had been lost due to transmitter failure or departure from the study area. All wolverines were fitted with radio transmitters, which were surgically implanted by Don Betts, DVM and Colin Gillin, DVM. F401 was confirmed pregnant by visual observation of one fetus during surgery. Serum progesterone levels were determined for the three females that were captured. F401, F404, and F402 had serum progesterone levels of 8.06ng/ml, 4.26ng/ml, and 0.12ng/ml respectively. M304 was originally captured in January 2001, and disappeared in April 2001, and after extensive searches the pilot could not locate him. We recaptured him on March 23, 2002 with a functioning transmitter, indicating that perhaps he had left the study area during the period that we could not locate him. We replaced his radio transmitter and fitted him with a GPS collar (see below). Den Locations & Spring Capture Effort.Telemetry locations of both F401 and F404 became localized at the end of February indicating that perhaps both these females were denning. One month after localizing, F401 began making extensive movements, which led us to believe that perhaps she had lost her kits, if in fact she had given birth. F404 remained in the same area with only small movements throughout the spring. On three trips into her localized area we found many wolverine tracks but never made a visual observation nor heard her radio signal. On one occasion we saw what we thought might be one set of kit tracks with adult tracks, but because of the snow conditions, this could not be confirmed. The adult tracks led into and out of a series of tunnels made from downed logs and snow. For fear of disturbing a potential den site, these structures were not thoroughly investigated. In early June, Gary Lust from Mountain Air Research located F404 three times a day for two consecutive days in the same area. On June 5 we went in on the ground in an attempt to locate her with her potential kits. We tracked her to a snow tunnel but were not successful in trying to dig her out. Instead, we sat on a hill and watched her leave the tunnel. Five hours later we observed another unmarked adult wolverine also leave the tunnel. Likely this adult was a male wolverine and the two were paired for mating purposes. We saw no evidence of kits. On May 24, on our first attempt to retrieve M304's dropped GPS collar, we hiked into the area where F401 had localized during late February through March. We followed wolverine tracks to a tunnel made from downed logs and snow, and saw what could have been kit tracks in the tunnel. These tracks, however, were also not confirmed. We saw ungulate hair and scat in this tunnel, both of which we collected for identification. Home Ranges. Each wolverine was located approximately once per week between the animal's capture date (Table 2) and June 30, 2002. Home ranges have not yet been calculated. Mortalities. On January 29, M561's radio transmitter was found signaling mortality in Cascade Canyon within GTNP. A trip into the mountains indicated that the signal from his radio transmitter was coming from a recent avalanche path. Because avalanche danger was still high, we did not attempt to pinpoint his location and dig him out on that date. Various attempts to retrieve his body during the winter were canceled due to safety concerns. Finally, on April 19 his body was retrieved from under 2.4m (8 ft.) of snow. When he was uncovered he was found lying on his side with his eyes open, three of his feet curled toward his mouth, and his front left leg twisted to the side. His last active signal was located on January 23. Avalanche danger during the six days when he could have died was rated as "considerable" to "high" by the Bridger-Teton National Forest Backcountry Avalanche Hazard and Weather Forecast. Additionally, an earthquake rated 3.7 on the Richter Scale occurred on January 28 at 9:30 PM, epicenter Kelly, WY, approximately 29 km from Cascade Canyon. A necropsy performed by Kathy Quigley and Neil Anderson of Montana Fish, Wildlife, and Parks on June 26 showed no indication that the wolverine died from trauma, nor any obvious signs of bruising. We found white striations in the wolverine's intercostal muscles indicating that the muscles may have been stressed in trying to breathe and that perhaps the wolverine died from suffocation. The wolverine's stomach was empty. Winter Recreation Use.?Winter recreational use surveys were completed from the air approximately once per week. During these surveys the pilot marked the location of any snowmobile or ski tracks seen from the air with a GPS unit. During these surveys the approximate age of the tracks was also recorded. These data have not yet been analyzed, but we plan to compare winter recreational use with wolverine locations and habitat use using GIS software during Fall 2002. These methods will be meshed with those tested ion the MRSA this winter in order to complete the winter recreation survey methodology.

Keywords: Greater Yellowstone Ecosystem, animal, mammal, wolverine, Gulo gulo, wildlife, management, population, mortality, Grand Teton National Park, Teton Mountain Range, Jackson Hole, human activity, radio collar, trapping, marten, Martes americana, fox, canine, Canidae, red fox, Vulpes vulpes, coyote, Canis latrans, den, denning, breeding