Evaluation of marked-recapture for estimating striped skunk abundance

Raymond J. Greenwood; Alan B. Sargeant; Douglas H. Johnson

doi:10.2307/3801526

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Evaluation of marked-recapture for estimating striped skunk abundance

Raymond J. Greenwood·Alan B. Sargeant·Douglas H. Johnson

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Abstract

The mark-recapture method for estimating striped skunk ( Mephitis mephitis ) abundance was evaluated by systematically livetrapping a radio-equipped population on a 31.4-km2 study area in North Dakota during late April of 1977 and 1978. The study population was 10 females and 13 males in 1977 and 20 females and 8 males in 1978. Skunks were almost exclusively nocturnal. Males traveled greater nightly distances than females (3.3 vs. 2.6 km, P < 0.05) and had larger home ranges (308 vs. 242 ha) although not significantly so. Increased windchill reduced night-time activity. The population was demographically but not geographically closed. Frequency of capture was positively correlated with time skunks spent on the study area. Little variation in capture probabilities was found among trap-nights. Skunks exhibited neither trap-proneness nor shyness. Capture rates in 1977 were higher for males than for females; the reverse occurred in 1978. Variation in individual capture rates was indicated among males in 1977 and among females in 1978. Ten estimators produced generally similar results, but all underestimated true population size. Underestimation was a function of the number of untrapped skunks, primarily those that spent limited time on the study area. The jackknife method produced the best estimates of skunk abundance.

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Journal of Wildlife Management Article

Source-reported bounding extent: 45.935238° to 49.000687° latitude; -104.048736° to -96.554507° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Raymond J. Greenwood, Alan B. Sargeant, Douglas H. Johnson. 1985. Evaluation of marked-recapture for estimating striped skunk abundance. https://doi.org/10.2307/3801526

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