Population Dynamics of Deer Mice, Peromyscus maniculatus, and Yellow-pine Chipmunks, Tamias amoenus, in Old Field and Orchard Habitats


  • Thomas P. Sullivan Agroecology Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia V6T 1Z4
  • Druscilla S. Sullivan Applied Mammal Research Institute, 11010 Mitchell Avenue, Summerland, British Columbia V0H 1Z8
  • Eugene J. Hogue Pacific Agri-Food Research Centre, Agriculture and Agri-Food Canada, 4200 Highway 97, Summerland, British Columbia V1X 7S3




Deer Mouse, Peromyscus maniculatus, Yellow-pine Chipmunk, Tamias amoenus, abundance, demography, old field, orchard, population dynamics, recruitment, reproduction, British Columbia


There are often several rodent species included in the small mammal communities in orchard agro-ecosystems. This study was designed to test the hypothesis that the population levels of Deer Mice (Peromyscus maniculatus) and Yellow-pine Chipmunks (Tamias amoenus) would be enhanced in old field compared with orchard habitats. Rodent populations were intensively livetrapped in replicate old field and orchard sites over a four-year period at Summerland, British Columbia, Canada. Deer Mouse populations were, on average, significantly higher (2.5 – 3.4 times) in the old field than orchard sites in summer and winter periods. Mean numbers/ha of Deer Mice ranged from 12.1 to 60.4 in old field sites and from 3.3 to 19.9 in orchard sites. Breeding seasons in orchards were significantly longer than those in old field sites, in terms of proportion of reproductive male Deer Mice. Recruitment of new animals and early juvenile survival of Deer Mice were similar in orchard and old field sites. Populations of Yellow-pine Chipmunks ranged in mean abundance/ha from 5.6 – 19.0 in old field sites and from 1.9 – 17.5 on one orchard site, with no difference in mean abundance in 2 of 4 years of the study. Recruitment and mean survival of Yellow-pine Chipmunks also followed this pattern. This study is the first detailed comparison of the population dynamics of these rodent species in old field and orchard habitats. These species should be able to maintain their population levels and help contribute to a diversity of small mammals in this agrarian landscape.