| The skull and jaws of the Yuma myotis suggest a dependence on relatively soft insects, and the little dietary information available supports this. It fits well with the bat's habit of foraging over water, where moths and other soft-bodied insects tend to be common. The bats are often seen cruising back and forth just a few inches above the water, and have never been found living far from a pond or river. In captivity, if they do not have water, they quickly become dehydrated and die. Groups of bats roost together in the summer, under bridges, in buildings, mines, or caves, and even in mud nests made by cliff swallows. This species varies in size and coat coloration over its extensive north-south geographic distribution, sometimes making it difficult to distinguish them from the closely related little brown bat. So far, genetic studies have shown them to be two distinct species, however.
Allen, H., 1864. Smithsonian Miscellaneous Collection, 7:58.
Mammal Species of the World
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