Demography of Sonoran Desert Tortoises

Demographic processes that govern dynamics of animal populations often vary spatially, but few population viability analyses account explicitly for that variation. To address this issue, we developed a model that produces spatially explicit estimates of demographic rates and population viability by incorporating spatial autocorrelation into analyses of local demographic information. We applied the model to demographic data collected across the geographic range of the Sonoran desert tortoise (Gopherus morafkai) in Arizona. Estimated rates of population change, λ, were near one, but varied regionally because of variation in adult and juvenile survival and the rate at which juveniles transitioned to adults. These photographs illustrate the article “A spatially explicit hierarchical model to characterize population viability” by S. P. Campbell, E. R. Zylstra, C. R. Darst, R. C. Averill‐Murray, and R. J. Steidl, published in Ecological Applications. https://doi.org/10.1002/eap.179