Greater Mastiff Bat

Eumops perotis

The western mastiff bat (Eumops perotis), also known as the western bonneted bat, the greater mastiff bat, or the greater bonneted bat, is a member of the free-tailed bat family, Molossidae. It is found in the Western United States, Mexico and South America. This species is the largest bat native to North America, and some of its distinguishing characteristics are its large ears, wings, and forearms. The subspecies Eumops perotis californicus is a species of concern as identified by the U.S. Fish and Wildlife Service. The range of this subspecies is principally southwest desert regions of the United States, along the border with Mexico; however, the range extends as far north on the Pacific coast as Alameda County, California.