Why are some wild animals more tolerant to human interaction than others?

photo+by+Daniel+T.+Blumstein,+2015_14232f72-9ecb-44d9-bcff-c914b85344c8-prvWhen most wild animals first encounter humans, they respond as they would to any predator — by running, swimming or flying away. Over time, some species become more tolerant of humans’ presence, but the extent to which they do is largely driven by the type of environment in which the animals live and by the animal’s body size, according to a comprehensive new analysis. Researchers led by Daniel Blumstein, a professor and chair of ecology and evolutionary biology in the UCLA College, analyzed 75 studies conducted over the past half-century of 212 animal species — mostly birds, but also mammals and lizards. The scientists estimated species’ tolerance to human disturbance by comparing how far away from humans an animal would have to be before it fled — a statistic called “flight initiation distance.”

The new analysis showed that larger animals are more likely to be disturbed in more remote areas by people, but if the human–animal interactions are mostly benign, and if the animals can tolerate people, larger species eventually learn that people are not very threatening. “This new finding flips previous recommendations about large-bodied species being more vulnerable to the presence of humans, and shows that large-bodied species are more tolerant,” said Blumstein, the study’s senior author and a member of the Institute of the Environment and Sustainability. “It is likely costly for animals to respond fearfully to people that are not harming them. The key question to ask now is which species can tolerate humans enough so as to habituate to them.”

Read the full article here.

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