A metapopulation model of social group dynamics and disease applied to Yellowstone wolves

Proceedings of the National Academy of Sciences
By: , and 



The population structure of social species has important consequences for both their demography and transmission of their pathogens. We develop a metapopulation model that tracks two key components of a species’ social system: average group size and number of groups within a population. While the model is general, we parameterize it to mimic the dynamics of the Yellowstone wolf population and two associated pathogens: sarcoptic mange and canine distemper. In the initial absence of disease, we show that group size is mainly determined by the birth and death rates and the rates at which groups fission to form new groups. The total number of groups is determined by rates of fission and fusion, as well as environmental resources and rates of intergroup aggression. Incorporating pathogens into the models reduces the size of the host population, predominantly by reducing the number of social groups. Average group size responds in more subtle ways: infected groups decrease in size, but uninfected groups may increase when disease reduces the number of groups and thereby reduces intraspecific aggression. Our modeling approach allows for easy calculation of prevalence at multiple scales (within group, across groups, and population level), illustrating that aggregate population-level prevalence can be misleading for group-living species. The model structure is general, can be applied to other social species, and allows for a dynamic assessment of how pathogens can affect social structure and vice versa.

Publication type Article
Publication Subtype Journal Article
Title A metapopulation model of social group dynamics and disease applied to Yellowstone wolves
Series title Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.2020023118
Volume 118
Issue 10
Year Published 2021
Language English
Publisher National Academy of Sciences
Contributing office(s) Northern Rocky Mountain Science Center
Description e2020023118, 10 p.
Google Analytic Metrics Metrics page
Additional publication details