Demographic response of a grassland rodent to environmental variability

TitleDemographic response of a grassland rodent to environmental variability
Publication TypeJournal Article
Year of Publication2007
AuthorsReed, AW, Kaufman, GA, Sandercock, BK
JournalJournal of Mammalogy
Pagination982 -988
Accession NumberKNZ001076
KeywordsClimate change, deer mouse, life-table response experiment, matrix model, Peromyscus maniculatus, prairie, stochastic model

We used stage-structured matrix population models, derived from 3 years with disparate levels of precipitation, to assess the potential effects of climate change on annual population growth (λ) of deer mice (Peromyscus maniculatus). Populations of deer mice increased during a year of normal precipitation (λ = 1.69 ± 0.02 SE) and a wet year (λ = 1.03 ± 0.02), but declined in a dry year (λ = 0.34 ± 0.02). Life-table response experiment analyses indicated that reduced survival of adults in the dry year, and reduced survival of pups and juveniles in the wet year, exerted the greatest influence on variation in population growth. Stochastic models that projected populations of deer mice for a 50-year period predicted that populations would not be able to persist if mean annual precipitation was reduced ≥11% by increasing the frequency of dry years. Furthermore, the stochastic population growth rate declined more quickly when the probability of a normal year was reduced, simulating increased variability in rainfall, relative to other scenarios examined. Our stochastic models indicate that a relatively small reduction in mean precipitation could result in substantial population declines of P. maniculatus in the mixed-grass prairie of central North America.