Graduation Date
Fall 2024
Document Type
Thesis
Program
Master of Science degree with a major in Natural Resources, option Wildlife
Committee Chair Name
Richard Brown
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
Barbara Clucas
Second Committee Member Affiliation
HSU Faculty or Staff
Third Committee Member Name
Ho Yi Wan
Third Committee Member Affiliation
HSU Faculty or Staff
Keywords
Activity patterns, American pika, Behavior, California, Camera traps, Community structure, Small mammals
Subject Categories
Wildlife
Abstract
COMPOSITION, SPATIAL CO-OCCURRENCE, AND TEMPORAL OVERLAP OF SMALL MAMMAL SPECIES AT AMERICAN PIKA (OCHOTONA PRINCEPS) ACTIVITY CENTERS
Understanding how spatial, temporal, and behavioral factors play a role in shaping the structure of small mammal communities can provide insights into the extent to which species can coexist. I investigated the community structure of American pikas (Ochotona princeps) and sympatric small mammals at lower elevations in Lassen National Forest, California, U.S.A. Camera trapping stations were installed at 35 activity centers of pikas across three study sites in Lassen National Forest from June - October 2023. I assessed differences in composition, spatial co-occurrence, and temporal overlap in communities of pikas and sympatric small mammals. A total of 11 small mammal species were detected. Community compositions differed significantly across sites, with California ground squirrels (Otospermophilus beecheyi) and a muskrat (Ondatra zibethicus) only occurring at one site. Observed spatial co-occurrence frequencies mostly did not deviate from expected co-occurrence frequencies among small mammals, except Douglas’s squirrels (Tamiasciurus douglasii) were positively associated with golden-mantled ground squirrels (Callospermophilus lateralis) and long-tailed shrews (Sorex sp.), and no negative associations were detected. The following temporal activity patterns were observed: bushy-tailed woodrats (Neotoma cinerea), deer mice (Peromyscus sp.), and long-tailed shrews were nocturnal while western chipmunks (Neotamias sp.), golden-mantled ground squirrels, and California ground squirrels (Otospermophilus beecheyi) were diurnal, and pikas and Douglas’s squirrels were crepuscular. Pikas temporally overlapped the least with bushy-tailed woodrats and the most with Douglas’s squirrels. Pikas and all small mammals temporally overlapped the least when pikas were haypiling. Behaviors displayed by pikas that had the highest temporal overlap with sympatric small mammals were mostly territorial. The type of territorial behavior used by pikas was associated with whether small mammals were diurnal or nocturnal. This study demonstrates that spatial, temporal, and behavioral factors play a role in shaping the community structure of pikas and sympatric small mammals. Findings from this study suggest that temporal partitioning and behavioral mitigation facilitate coexistence between pikas and sympatric small mammals.
Citation Style
Journal of Wildlife Management
Recommended Citation
Giudici, Tina, "COMPOSITION, SPATIAL CO-OCCURRENCE, AND TEMPORAL OVERLAP OF SMALL MAMMAL SPECIES AT AMERICAN PIKA (OCHOTONA PRINCEPS) ACTIVITY CENTERS" (2024). Cal Poly Humboldt theses and projects. 812.
https://digitalcommons.humboldt.edu/etd/812
Collaboration
1