Western Mastiff Bat

Western Mastiff Bat
Eumops perotis

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Wingspan: 21 – 23"; Body length: 4 1/3 – 6 1/2”
Diet: insects

Tonto National Monument is one of the few sites in Arizona where this remarkable bat, the largest in North America, has been found. Mastiff bats are too heavy to launch themselves into flight from the ground as other bats can, and must drop from a high perch. Probably the cliffs above the Lower Cliff Dwelling are ideal for this purpose.

Mastiff bats receive their name from their dog-like faces. Unlike most bats, they make a distinctive sound that can be heard by the human ear. However, most of their sounds are ultrasonic, or emitted at a very high frequency, and cannot be heard by humans.

All North American bats use such sounds, produced in the throat, to navigate in darkness and to find food. The bat's extremely keen hearing picks up the echoes of these sounds off flying insects, allowing the bats to home in on their prey.

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26260 N AZ Hwy 188 Lot 2
Roosevelt, AZ 85545


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