Bats, belonging to the Order Chiroptera, are the only mammals capable of true and sustained flight. With over 1,500 identified species, bats represent the second-largest order of mammals globally. This vast biological diversity is reflected in their feeding habits, which span the full spectrum of animal diets. Depending on the species, a bat may be classified as a carnivore, a herbivore, or an omnivore.
Herbivorous Bats
A significant portion of the world’s bat population feeds exclusively on plant matter, classifying them as herbivores. These bats are generally divided into two main dietary groups: frugivores, which consume fruit, and nectarivores, which feed on nectar and pollen.
Frugivorous bats, often referred to as fruit bats or flying foxes, primarily subsist on the pulp and juices of ripe fruits. They use specialized teeth adapted for crushing, such as large canines and non-molariform premolars, to mash the fruit and extract the nutrient-rich liquids. Frugivorous species act as seed dispersers, often carrying fruit away from the parent plant to a feeding roost before consuming it and excreting the seeds elsewhere. This aids in forest regeneration. For example, the great fruit-eating bat (Artibeus lituratus) is known to switch between multiple fruit trees in a single night, effectively spreading seeds over a wide area.
Nectarivorous bats have evolved to consume energy-rich nectar and protein-rich pollen from flowering plants. These bats exhibit specialized morphology, including long, narrow snouts and greatly reduced cheek teeth. Their tongues are frequently elongated and possess fine, brush-like papillae at the tip to efficiently collect nectar from deep within flowers. These species are effective pollinators, transferring pollen between plants as they feed, a role comparable to that of bees or hummingbirds in the ecosystem.
Carnivorous Bats
The largest number of bat species are insectivores, which places them within the carnivorous category, as they consume animal matter. Approximately 70% of all bat species feed primarily on insects and other arthropods, such as spiders. These microbats are proficient hunters, using echolocation to locate and track flying insects like moths and beetles in complete darkness. Their teeth are typically sharp, with cusped cheek teeth adapted for cutting and breaking down the chitinous exoskeletons of their prey.
Beyond insects, a smaller but specialized group of bats preys on larger animals, including small vertebrates. These specialized hunters have evolved the ability to consume fish, frogs, lizards, birds, and rodents. An example is the fringe-lipped bat (Trachops cirrhosus), which can locate frogs by listening for their calls, demonstrating a reliance on prey-generated sound cues rather than only echolocation.
Piscivorous bats, such as the greater bulldog bat (Noctilio leporinus), are specialized for catching fish directly from the water’s surface using their large, sharp claws. Carnivorous bats that consume terrestrial vertebrates, like the spectral bat (Vampyrum spectrum), tend to be larger than insectivores and possess elongated snouts and strong jaws to subdue their prey. The spectral bat, the largest carnivorous bat in the New World, hunts small birds and mammals weighing up to its own body weight.
Omnivores and Highly Specialized Diets
Many bat species do not fit neatly into a single herbivore or carnivore classification because they are omnivores, regularly consuming both plant matter and animals. A species might primarily eat fruit but supplement its diet with insects when available, or vice-versa, depending on seasonal resource availability.
The Phyllostomus genus contains several broadly omnivorous species, such as Phyllostomus hastatus, which is known to consume a wide diet ranging from pollen and fruit to insects and small vertebrates. These generalist feeders often possess a more equal allocation of space to different types of teeth, reflecting the need to process diverse food textures, from soft fruit to hard insect exoskeletons.
A specialized dietary category is sanguivory, or blood-feeding, practiced exclusively by the three species of vampire bats. The common vampire bat (Desmodus rotundus) feeds mainly on the blood of mammals, while the hairy-legged and white-winged vampire bats primarily target birds. These bats have evolved razor-sharp incisors to make a small, precise incision and an anticoagulant in their saliva to keep the blood flowing while they lap it up. Vampire bats possess a gut microbiome adapted to process a challenging, high-protein diet, and the ability to maneuver on the ground to approach their sleeping hosts.