Semester

Summer

Date of Graduation

2000

Document Type

Dissertation

Degree Type

PhD

College

Davis College of Agriculture, Natural Resources and Design

Department

Wildlife and Fisheries Resources

Committee Chair

Petra Bohall Wood.

Abstract

The Allegheny woodrat occurs throughout the Appalachian Mountains, where it forms isolated colonies in rock outcrops, cliffs, and caves. Populations along the northern and western peripheries of the range have experienced drastic declines in the past 20--30 years. A paucity of ecological information is available for this species, particularly regarding the effects of anthropogenic disturbance. Furthermore, no information is available on population structure, gene flow, or relatedness among colonies. The objectives of my study were to examine the impacts of forest management practices on movements, home range, and habitat use and to determine genetic structure and levels of gene flow within and among Allegheny woodrat populations.;I used radiotelemetry to examine home range, movements, and habitat use, at colony sites representing two timber harvesting methods, clearcutting and diameter-limit harvesting, and unharvested controls. Home range and foraging distance estimates were calculated from telemetry locations and compared among treatments. Microhabitat variables were measured within plots centered around known foraging locations and compared with randomly selected plots within the home range.;Results suggest that timber harvesting has minimal impact on woodrat movements, home range, and habitat use in situations where intact forest is retained adjacent to colonies. Furthermore, timber harvesting did not influence microhabitat selection, as woodrats foraged in areas with diverse understory vegetation regardless of harvest method. Although timber harvesting appeared to have little negative impact, retention of intact forest near colonies should be an important consideration in management for this species.;I developed 11 polymorphic microsatellite DNA markers and examined Allegheny woodrat genetic variation at two spatial scales, geographically distinct regional populations and subpopulations within regional populations. The markers detected significant genetic variation and appear useful for population studies in this species. Additionally, cross-species amplification trials were successful in seven other Neotoma species. I detected significant genetic differentiation in Allegheny woodrat populations at both spatial scales examined. A significant relationship between geographic and genetic distance suggests isolation by distance as a mechanism for differentiation. Results suggest that individual colonies or aggregations of geographically proximate colonies function as populations and should be considered conservation units for management.

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