Date of Award

5-2007

Level of Access

Campus-Only Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Wildlife Ecology and Wildlife Conservation

Advisor

Daniel J. Harrison

Second Committee Member

Malcolm L. Hunter Jr.

Third Committee Member

William B. Krohn

Abstract

The Newfoundland marten (Martes americana atrata) is an endangered population of American marten (M. a. americana) endemic only to the island of Newfoundland. I documented home-range characteristics, habitat selection, survival rates, and cause specific mortality factors inside and outside a wildlife reserve, to provide insights into effects of anthropogenic influences (e.g., timber harvesting, snaring, and trapping) on marten populations. Median home-range areas of adult martens in Newfoundland (males = 27.6 km2, n = 43; females = 10.6 km2, n = 49) were disproportionately larger than those for a mainland marten population (males = 3.3 km2, n = 135; females = 2.4 km2, n = 91) in northcentral Maine. Allometric analyses revealed that home-range area of martens from Maine scaled approximately linearly with body weight whereas the relationship in Newfoundland was strikingly nonlinear, these differences being attributable to landscape configuration and prey abundance. Multi-scale habitat selection revealed that martens exhibited positive or neutral selection for a broad range of habitat types within their home ranges. Adult resident martens occupied home ranges that were not dominated by mature and overmature forest conditions. Selection for tall (> 12.5 m height) closed-canopied (> 50%) softwood stands, which based on previous work is required habitat for Newfoundland martens, was intermediate in relative preference, and comprised only 12.5% of home ranges. Age distributions were not different among martens with high, intermediate, and low amounts of mature and overmature forest in their home range. Further, survival of adult martens was not positively associated with increasing homerange availability of mature and overmature coniferous forest. I documented 52 mortalities during the study; human-caused mortality accounted for 45.3% of all mortalities and 71.9% of mortality outside the reserve. Models best characterizing survival of adults indicated a strong (positive) additive effect of increased habitat availability within the home range and increasing distance from roads where snowshoe hare (Lepus americanus) snaring and furbearer trapping of furbearers was legally permitted. Annual survival of adult martens (M = 112, F = 112) was 0.83 for both males and females. Survival of juvenile martens from October to April was 0.76 inside the reserve but only 0.51 in areas open to snaring and trapping. Marten populations outside the Pine Marten Study Area reserve are likely maintained by dispersal from the reserve or other untrapped refugia.

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