Browsing by Subject "wolf population"

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    2021-2022 Greater Voyageurs Ecosystem wolf pack and population size report
    (2022) Gable, Thomas D; Homkes, Austin T; Bump, Joseph K
    This report presents and discusses data on wolf population metrics collected during 2021-2022 in the Greater Voyageur Ecosystem, Minnesota. In 2021-2022, we estimated the area of 9 wolf pack home ranges/territories, determined the size of 14 wolf packs, and obtained 7.3 independent observations of the same size for each pack. The survey effort in 2021-2022 was the same as 2020-2021 and represents the most intensive survey effort, in terms of number of packs and territories studied, to date in the Greater Voyageurs Ecosystem. We estimate that wolf population density in the Greater Voyageurs Ecosystem in 2021-2022 was 63.2 wolves/1000 km2 (95% confidence interval: 50.3-83.8 wolves/1000 km2). This density represents a 16% increase in population density from 2020-2021 and a 48% increase from the recent population low in 2019-2020 of 42.7 wolves/1000 km2. The increase in population density is largely attributable to increased pup survival, which likely increased pack size. We compared current wolf population density and population metrics to historical wolf density and population metrics in the Greater Voyageurs Ecosystem. This assessment suggests that wolf density in the GVE has changed little since the late 1980's, and that the GVE has sustained a high-density wolf population for decades.
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    2022-2023 Greater Voyageurs Ecosystem Wolf Population Report
    (2023) Gable, Thomas D; Homkes, Austin T; Bump, Joseph K
    During April 2022-April 2023, we studied the wolf population in the Greater Voyageurs Ecosystem (GVE), Minnesota in an effort to understand wolf population dynamics and how changes in population dynamics are connected to or influence predation behavior, wolf pup survival, and changes in prey density. We estimated the area of 8 wolf pack home ranges/territories and estimated the size of 20 wolf packs based on an average of 11.7 independent observations of each pack at the estimated size (i.e., the number of wolves we determined were in a given pack). In total, we recorded 606 observations of 2 or more wolves traveling together during the winter survey period. The 2022-2023 survey effort was the most intensive survey effort to date in the Greater Voyageurs Ecosystem, Minnesota. We estimate that wolf population density in the Greater Voyageurs Ecosystem in 2022-2023 was 65.2 wolves/1000 km^2 (95% confidence interval: 53.7-87.8 wolves/1000 km^2), indicating that wolf density remained unchanged from 2021-2022 (65.7 wolves/1000 km^2). Although wolf density has varied annually in the GVE since 2015, there is no indication that wolf density has increased or decreased with time. In other words, the population has remained relatively stable and current population density (65.2 wolves/1000 km^2) is close to the average population density (60.4 wolves/1000 km^2) over the past 9 years (2015-2023) in the GVE.