Ever wondered what type of prey bats eat? In a previous post, I discussed the different hunting styles bats employ. These allow them to forage for their prey in a wide range of situations.
Firstly, we can split prey into flying and non-flying groups.
Flying bat prey
Lepidoptera (Butterflies and moths)
Butterflies and moths are common bat prey items and can form the majority of the diet for bats like barbastelle. Once the bat has eaten the body, the wings are typically discarded. This leaves subtle clues that a bat has been present.
It is estimated that a pipistrelle bat can eat 3000 midges in one night! Flies also form the part of the diet of many other bat species. Many of these species are considered nuisance/pest species, highlighting the role bats play in pest control.
Hymenoptera (Ants, bees, and wasps)
This group forms only a minor part of a bat’s diet, largely due to the fact that they are active at different times of day. On face value, the fact that bats eat stinging insects may seem odd, however this group is very broad with the majority of species not containing a sting.
Named after their delicate, see-through wings, lacewings are carnivorous insects, feeding on sap-sucking bugs like aphids. Lesser horseshoe bats will take these prey. Like butterfly and moth wings, you may be able to find the discarded wings of lacewings beneath feeding perches.
Hemiptera (True bugs)
True bugs have piercing mouth pieces, which distinguishes them from other small insects. The term ‘bug’ is a colloquialism used to refer to a range of small invertebrates. The piercing mouth piece allows bugs to tap into a plants vascular system and extract sap. Serotine bats use their big teeth to crunch through the hard cases of bugs.
These aquatic insects live as nymphs under the water for several years. When they mature, they emerge from the water in the spring, often en masse. This can provide rich pickings for bats with a preference for riparian habitats, such as soprano pipistrelle.
Similar to mayflies, caddisflies live as aquatic larvae for several years. Most surround themselves with portable protective casing, constructed from material found in their environment. Underwater they must evade fish in the water; once they emerge, Daubenton’s bat may be waiting to pick them off.
Beetles come in a variety of shapes, colours and sizes. The largest UK species is the stag-beetle. Whilst our larger bat species may take these, smaller bat species target other beetle species. Cockchafers (or maybugs) are a firm favourite of our larger bat species, such as noctule and greater horseshoe bat.
Non-flying bat prey
As well as catching prey on the wing, bats can also hunt by gleaning or hunt on the ground.
In their larval stage, butterflies and moths are relatively defenceless. Camouflage is their main defence. If they can find them, bats will happily take caterpillars from foliage. Brown long-eared bats use their large ears to listen for prey and pick them off.
Spiders/ harvestmen (Arachnida)
In my previous post, I shared this video of a Natterer’s bat taking a spider from its web (from David Attenborough’s Life of Mammals BBC series). This illustrates the point so well, I don’t think it needs any more explanation.
These are widespread, nocturnal insects. They are often blamed for damage to agricultural crops. Bechstein’s bat can land on the ground and forage for earwigs amongst the leaf litter. Again, highlighting the important role bats play in biological control
Orthoptera (Grasshoppers & crickets)
From late summer onwards, these species are well known for producing characteristic ‘chirping’ sounds. They create ultrasonic sounds by rubbing the hind legs against the forewings. When startled, they can jump considerable distances. Presumably, bats catch them whilst in the air.
Non-flying arthropods (Centipede, millipedes and woodlice)
Arthropods have segmented bodies and paired legs. The number of segments (and legs) varies between species. Typically found amongst damp organic matter, such as the leaf litter of a woodland. In these locations, they either predate other small invertebrates or feed on decaying organic matter. Whiskered bats are partial to these animals.
Ground beetles (Coleoptera)
Like their flying counter-parts, ground beetles come in a variety of shapes, colours and sizes. Their wing cases are fused, which means they have lost the ability of flight. They are predators, taking any invertebrate they can overpower. Unfortunately for them, certain bats can overpower them!
Want to learn more?
To find out more about the prey species bats take, and the plant species the prey are associated with, see this document from the Bat Tree Habitat Key project.