Anthropogenic environmental change and habitat occupancy by riparian muskrats in a Midwestern landscape

muskrat;Ondatra zibethicus;landscape ecology;occupancy modeling;urban adapter;Phalaris arundinacea;imperfect detection;predictive habitat model

Bucci, Lisa A. ; Schooley ; Robert L.

关键词: muskrat;    Ondatra zibethicus;    landscape ecology;    occupancy modeling;    urban adapter;    Phalaris arundinacea;    imperfect detection;    predictive habitat model;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/14764/Bucci_Lisa.pdf?sequence=4&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Increased urban land cover and more intensive agriculture in the Midwest have changed the landscape for wildlife species. Distributions of semi-aquaticmammals such as muskrats (Ondatra zibethicus) may respond to environmental changes including increased urbanization, alteration of hydrology, introduction ofinvasive species, and changes in predator communities. The response of muskrat populations to landscape and local-scale changes is important for the conservationof this economically-valuable furbearer species. I completed multiple surveys for occupancy by muskrats at 90 sites in central Illinois in 2007 and 2008. Sites were stratified based on urbanization levels. Occupancy was determined by presence of tracks, scat, and feeding sign in 200-m stream segments that approximated ahome-range scale. I calculated detection probabilities to determine the likelihood of false absences. The per-survey detection probability was 0.79 (SE = 0.04) in2007 and 0.76 (SE = 0.04) in 2008. Detection was related positively to Julian date and negatively to wood debris abundance. Muskrats occurred more often at sites with a greater percentage of developed landcover, as well as in wider anddeeper streams that drained more area. Year-to-year turnover was explained by water availability and measures of stream size. Although invasive reed canarygrass was the dominant species at an average of 2.3 (SE = 0.20) out of 5 habitat sampling stations per site, it did not affect site occupancy or turnover. Occupancypatterns may be related to lower predation risk near human development and in wider, deeper streams. Overall, muskrat distribution was related to local and landscape variables and was insensitive to some aspects of environmental change.