The majority of the fish-eating myotis’s diet comprises oceanic species (6), primarily fish (7). The fish-eating myotis hunts at night, when it flies over the ocean searching for ripples in the water that indicate a fish swimming near the surface (8). The fish-eating myotis snatches the fish using its long feet, large toes and sharp, curved claws, and transfers the fish to its mouth (7) (8). The fish is then consumed during flight or when the bat has settled at a nearby roost (7). The fish-eating myotis is able to catch and eat around 30 fish each night (8). The fish-eating myotis also feeds on small crustaceans and some flying insects, both of which are believed to be caught in the mouth (7). Remarkably, the fish-eating myotis is able to drink seawater (9).
The gestation period in the fish-eating myotis is about 55 days, with females generally giving birth to a single pup in late May or early June (2). In early June females may be seen carrying the young on one of the teats (7). The young bat may remain on the mother for up to three weeks, after which it will not leave the roost until able to fly, at about seven weeks old (2).
The fish-eating myotis is preyed on by a number of seabirds, and predatory gulls have been observed inspecting rock crevices in search of this bat (2).