(Phys.org)—An international team of researchers working in a part of Arizona has found evidence of a hummingbird species benefiting by building nests in trees beneath hawk hunting grounds. In their paper published in the journal Science Advances, the team describes the study they carried out and just how much safer the hummingbirds appeared to be when living in close proximity to hawks.
To learn more about black-chinned hummingbirds living in Arizona’s Chiricahua Mountains, the team walked among the trees looking up, as part of a three year study of hummingbirds living beneath 12 hawk nests. In so doing, they discovered that hummingbird nests beneath hawks were approximately 80 percent safer from Mexican jays eating their eggs than were unprotected nests.
There were two types of hawks involved in the study, Cooper and goshawks, both find food by looking down from their perch high in a tree—when they spot something, such as a jay, they swoop down between the branches and grab their meal. They don’t generally target hummingbirds, however, the team noted, likely because they are too small and fast. That led to what the researchers call cones of protection, where nests within a certain area under a hawk’s nest would be protected by the hawks. Jays, they noted, were more likely to fly higher in such areas, above the cone.
Hummingbirds find protection building nests under hawks