In arid and semi-arid environments, primary productivity tracks the highly variable patterns of temperature and rainfall events. These patterns can have pronounced and oftentimes little understood consequences for the population dynamics of small mammal populations that thrive in resource-restricted environments. We used a 20-year capture-recapture data set collected each spring and fall in mixed oak woodland in coastal-central California to investigate the vital demographic rates of the pinyon mouse (Peromyscus truei). We examined links between this species’ demography and a suite of environmental and bioclimatic factors. We applied Pradel’s temporal symmetry model, which allowed for simultaneously estimating capture probability, realized papulation growth rate, and apparent survival in this population.
Results/Conclusions
Capture probabilities varied seasonally (higher in fall), and as a function of sex. Females showed relatively higher capture rates. Although the population was stable during the 20 years of study (realized population growth rate, λ = 0.99 ± SE 0.0002), seasonal growth rate was highly variable, ranging from 0.78 ± 0.02 to 1.31 ± 0.03. Overall monthly survival was 0.82 ± 0.003, but varied over time and differed between sexes, with estimates ranging from 0.64 ± 0.07 to 0.90 ± 0.01. Monthly recruitment rate ranged from 0.02 ± 0.01 to 0.43 ± 0.02. In our talk, we report the relative impacts of temperature, rainfall, and resource availability patterns on these vital demographic rates. Discerning linkages between species’ population dynamics and environmental stochasticity are critical for understanding the impacts of global climate change, and for gauging the viability and resilience of populations in resource-restricted environments.