A new study co-authored by researchers at the University of California Los Angeles and the Max Planck Institute for Animal Behavior reveals how changing climate conditions influence the social and foraging behaviors of white-faced capuchin monkeys, according to a May 6 statement. The research is based on more than three decades of data collected from 12 groups of capuchins in Costa Rica’s Lomas Barbudal Monkey Project.
The findings provide insight into how animal societies may respond to increasingly extreme weather events, which are expected to become more common in the future. Long-term studies like this one help scientists predict animal responses to such changes, according to the researchers.
The study found that larger groups of capuchins had lower feeding rates, especially during periods of extreme climate conditions. Home range size expanded with group size, but daily travel distance did not increase as expected. “It seems that larger groups compensate for the larger number of mouths to feed not by traveling further each day, but by having a larger variety of resources they can visit, which allows them to visit less depleted food patches,” Susan Perry said.
Researchers observed that during Costa Rica’s dry season, resources became concentrated along rivers and competition between groups intensified. Larger groups were able to dominate higher-quality areas while smaller groups were pushed into less productive parts. Lead author Odd Jacobson said: “This was a clear sign that the group members were competing with each other, which is what we expected for large groups.” He added: “In doing so, large groups could offset the costs of internal competition.”
Extreme weather events such as El Niño and La Niña increased challenges for large groups by intensifying competition and reducing their advantages over smaller ones. Perry said: “But under climatic extremes, that buffer reaches its limits, and monkeys may adjust by making changes to group size, for example, by dispersing to other groups.” She also noted: “Long-term data sets such as this one are so valuable scientifically that they make the hardships seem worthwhile.”
The University of California Los Angeles has been associated with notable figures including Nobel laureates and MacArthur Fellows; it fosters diverse perspectives through academic programs on its 419-acre campus within the University of California system according to the official website.