California Leaf-nosed Bat - Foraging Habits

Foraging Habits

This bat is a "gleaning" insectivore which captures prey such as crickets, grasshoppers, beetles, and sphinx moths straight from the ground or foliage rather than in flight. It prefers to use its large eyes to detect prey, although in total darkness it will switch to echolocation. It typically hunts within a few feet of the ground, using its superior eyesight to search for insects. It does not alight to capture its prey, but hovers above it and snags it off the substrate. It then carries its prey to an open roost such as a porch or open building to dismember, then consume it.

These bats usually forage within three feet of the ground and often drop down closer to the ground nearer the surface where they can occasionally hover for a few seconds. Even bats released in the daytime flew fairly close to the ground. Leaf-nosed bats seem to be totally insectivorous, and their food clearly reflects the bats’ foraging habits. Some insects regularly eaten by Macrotus are almost certainly taken from the ground or from vegetation. The bats’ stomachs often contain orthopteran insects, noctuid moths and caterpillars, and beetles of the families Scarabaeidae and Carabidae, along with unidentified material. The lists of food items of Macrotus contain a plethora of insects that seldom fly, are flightless, or that fly in the daytime. This constitutes strong evidence that this bat consumes insects that are on the ground or on vegetation. Most leaf-nosed bats forage sometime between one hour after sundown and four hours after sundown, and then retire to a night roosting place. Each bat seems to have a pre-midnight foraging period of roughly one hour. The greatest activity in the early morning seems to occur between two and one half hours before sunrise and thirty minutes before sunrise. Bats generally begin returning with full stomachs to their daytime roosts about two hours before sunrise, and the last bats usually return approximately twenty minutes before sunrise.