It is very common all over the places except in the Deep South and in the northern states and it is unknown in Florida and central Texas. Its summer and winter ranges are identical. Diet E. fuscus is a carnivore and feeds on different kind of insects. They eat insects like, true bugs, flying ants or braconids. E. fuscus is an efficient feeder.
Adults can fill their stomach in about an hour.
Once they dected their prey they catch it with their wing membrane. They wrap their wings around their prey like a blanket. Then they use their feet to pass the food to their mouth. Some big brown bats may also capture their food on the ground, so they swoop down on them. Habitat Their favorite places are porches of stucco or brick houses, garages with open doors, or a breeze way.