What Bats Eat

Bats are successful throughout the world due in large part to their proficiency as predators of all night flying insects.  Between 60 and 70% of all bats are insectivores. Almost any insect that is active at night can be food for a bat, including moths, beetles, flies, crickets, gnats, mayflies, wasps, and mosquitoes.

There are other bats that eat a wide variety of food: scorpions, fish, fruit, pollen, spiders, arthropods, nectar, small mammals, and non-flying insects. Ten species of bats in Central America are carnivorous, and they prey on small birds, small mammals, or other bats. One of these bats, the false vampire Vampyrum spectrum, hunts for its avian prey using its excellent sense of smell. Other carnivorous bats hunt by listening to prey generated sounds.

These bats also eat a significant number of arthropods, so it is likely that the carnivorous bats evolved from insectivorous ancestors. One genus of bats, Noctilio, trawls for small fish over the water. It uses its hind legs and specialized toe nails to snag the unsuspecting fish and then returns to a roost to feed. There are three bats that feed on blood. These are the famous vampire bats, whose foraging habits are responsible for giving many other bats a bad name. Some bats eat plant material. In the Old World the entire suborder Megachiroptera eats fruit and nectar, and in the Americas the Phylostomidae (of the suborder Microchiroptera) are also frugivorous.

In general, frugivorous bats tend to be larger than nectivorous bats. They have a more developed sense of smell and vision, and many roost in trees rather than caves. Frugivorous bats play a major role in the overall health of the tropical forests. They disperse the seeds of the fruit they eat which helps the forest regenerate after being cut down. The plants that rely on bats for seed dispersal usually have a strongly odored fruit that remains on the tree long after they are ripe. Often this fruit is on long stalks or positioned away from twigs and leaves. This allows for easy access for the bats, but makes it very difficult for birds to eat the fruit. The seeds of these plant are hard kernels that separate easily from the flesh of the fruit. Several species of bats are also important pollinators. There are more than twenty genera of plants that rely on bats to pollinate them, These plants range from blooming cacti to wild banana trees. The bats and plants have exhibited modifications, which increase the success of feeding and pollination.

Nectivorous bats have long muzzles and long protruding tongues that have a brush tip that gathers pollen quickly and efficiently. Flowers of the plants pollinated by bats angle downward, and shaped and sized just right for a bat to insert their head and shoulders. In fact, recent research has suggested that some flowers in the New World are shaped to reflect the echolocation calls of foraging bats so that they can find the pollen of that flower. Most have an abundance of nectar, open at night and have a strong smell.

Bats are extremely important members of a healthy rainforest, and by dispersing seeds they help to regenerate the forest after clear-cutting or fires. Every ecosystem is integrated in a similar manner, with each part depending on other parts of the ecosystem and being depended on in turn. Ecologists are concerned about the loss of biodiversity because we know that the loss of any species will affect all the other species in the ecosystem.

© 2012 Organization for Bat Conservation