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John W. Burch

Publications and source records attributed to John W. Burch.

7 recordsLinked to original sources

Evaluation of wolf density estimation from radiotelemetry data

Density estimation of wolves ( Canis lupus ) requires a count of individuals and an estimate of the area those individuals inhabit. With radiomarked wolves, the count is straightforward but estimation of the area is more difficult and often given inadequate attention. The population area, based on the mosaic of pack territories, is influenced by sampling intensity similar to the estimation of individual home ranges. If sampling intensity is low, population area will be underestimated and wolf density will be inflated. Using data from studies in Denali National Park and Preserve, Alaska, we investigated these relationships using Monte Carlo simulation to evaluate effects of radiolocation effort and number of marked packs on density estimation. As the number of adjoining pack home ranges increased, fewer relocations were necessary to define a given percentage of population area. We present recommendations for monitoring wolves via radiotelemetry.

Wildlife Society Bulletin

Serologic survey for canine coronavirus in wolves from Alaska

Wolves ( Canis lupus ) were captured in three areas of Interior Alaska (USA). Four hundred twenty-five sera were tested for evidence of exposure to canine coronavirus by means of an indirect fluorescent antibody procedure. Serum antibody prevalence averaged 70% (167/240) during the spring collection period and 25% (46/185) during the autumn collection period. Prevalence was 0% (0/42) in the autumn pup cohort (age 4-5 mo), and 60% (58/97) in the spring pup cohort (age 9-10 mo). Prevalence was lowest in the Eastern Interior study area. A statistical model indicates that prevalence increased slightly each year in all three study areas. These results indicate that transmission occurs primarily during the winter months, antibody decay is quite rapid, and reexposure during the summer is rare.

Alaska

Is incest common in gray wolf packs?

Wolf packs generally consist of a breeding pair and their maturing offspring that help provision and protect pack young. Because the reproductive tenure in wolves is often short, reproductively mature offspring might replace their parents, resulting in sibling or parent-offspring matings. To determine the extent of incestuous pairings, we measured relatedness based on variability in 20 microsatellite loci of mated pairs, parent-offspring pairs, and siblings in two populations of gray wolves. Our 16 sampled mated pairs had values of relatedness not overlapping those of known parent-offspring or sibling dyads, which is consistent with their being unrelated or distantly related. These results suggest that full siblings or a parent and its offspring rarely mate and that incest avoidance is an important constraint on gray wolf behavioral ecology.

Behavioral Ecology

Patterns of prey selection by wolves in Denali National Park, Alaska

The patterns of selection by wolves ( Canis lupu s) preying on moose ( Alces alces ), caribou ( Rangifer tarandus ), and Dall sheep ( Ovis dalli) in Denali National Park and Preserve, Alaska were studied from 1986 through early 1992. Wolves and their prey are legally protected or relatively unharvested in most of the area, and wolf numbers doubled during the study. Based on remains of 294 moose, 225 caribou, and 63 sheep, wolves killed calves and old adults disproportionately, and individuals with low marrow fat, jaw necrosis, or arthritis. Seasonal trends in proportions of various species, ages, and sex of kills were found. During the winters following winters of deep snowfalls, wolves greatly increased the proportion of caribou cows and calves taken. We conclude that in a natural system, wolves can survive on vulnerable prey even during moderate weather, and when snowfall exceeds average, they can respond by switching to newly vulnerable prey and greatly increasing their numbers.

Occasional Publication of the Canadian Circumpolar

Pack structure and genetic relatedness among wolf packs in a naturally-regulated population

Observations of wolf pack dynamics over a six-year period in Denali National Park and Preserve, Alaska, found high rates of intraspecific strife, wolf pack dissolution and new pack formation, and the acceptance of new wolves into established packs. These observations corroborate genetic studies that found more genetic links between packs, and more genetic diversity within packs, than would be expected if most packs were composed of an unrelated breeding pair and their offspring. Longevity of packs, stability of pack territories, and the incidence of inbreeding all appear to be less than previously suggested, even in the absence of significant human disturbance. The formation of new packs by two or more local dispersers, the acceptance of unrelated wolves into existing packs, and the presence of multiple breeding females within packs would tend to blur genetic distinctions between the packs in a population.

Occasional Publication of the Canadian Circumpolar

Denali Park wolf studies: Implications for Yellowstone

The Northern Rocky Mountain Wolf Recovery Plan approved by the U.S. Fish and Wildlife Service (1987) recommends re-establishment of wolves ( Canis lupus ) in Yellowstone National Park. Bills proposing wolf re-establishment in the Park have been introduced into the U.S. House and Senate. However, several questions have been raised about the possible effects of wolf re-establishment on other Yellowstone Park fauna, on human use of the Park and on human use of surrounding areas. Thus the proposed wolf re-establishment remains controversial. Information pertinent to some of the above questions is available from a current study of wolf ecology in Denali National Park and Preserve, Alaska, which we began in 1986. Although Denali Park differs from Yellowstone in several ways, it is also similar enough in important respects to provide insight into questions raised about wolf re-establishment in Yellowstone.

Transactions of the North American Wildlife and Na