Aerial Insectivores vs. Foliage Gleaners

Bats are typically classified as either "aerial insectivores" or "foliage gleaners."Most bats fall under the aerial insectivore classification. They use echolocation, also referred to as biosonar, to not only hunt and capture food (or to detect immobile food if they are foliage gleaners), but also to navigate their environment. They tend to have longer, narrower wings for foraging over long distances in little time. They travel far in one night and can either be loyal to an area or move to another location with another roosting area.

Foliage gleaners on the other hand, rather than detect the movement of prey, they use echolocation to map their environment in detail as well as listen for insect calls in order to locate immobile insects, fruits, and/or flowers.  A few bats with this foraging style actually don't use echolocation, but instead use keen eyesight to locate food.  Their wings are broad, giving them high maneuverability and allowing them to hover.  The wings also decrease their ability to fly long distances, so they tend to be loyal to an area where their food is abundant.  They typically have long, highly manueverable ears to hone in on specific locations.  The insect-hunters, because the prey is so large for them, generally have to go to a nearby roost where they pick off the extremities before ingesting the good parts.

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