( 471 ) 



THE MODE IN WHICH BATS SECURE 

 THEIR PREY. 



By Charles Oldham. 



Observations made during the past few months have to a 

 great extent confirmed my suggestion (ante, p. 51) that the 

 method adopted by the Whiskered Bat {Myotis mystacinus) and 

 the Long-eared Bat (Plecotus auritus) to secure their prey was 

 common to other species. This curious habit seems to be little 

 known, or, if noticed at all, to have been misunderstood,* and is 

 so remarkable that a further description of it, even at the expense 

 of repetition, will, I trust, be forgiven. 



When walking, most of our British Bats carry the tail curved 

 downward and forward beneath the body, the interfemoral mem- 

 brane forming a pouch or bag. If a moth or other large insect 

 be encountered, the Bat seizes it with a rapid snatch, slightly 

 spreading its fore limbs with the wings still folded, and, pressing 

 them firmly on the ground at the carpus in order to steady itself, 

 brings its feet forward in order to increase the capacity of the 

 pouch, into which, by bending its neck and thrusting its head 

 beneath its body, it pushes its prey. If the moth be a large one 

 the Bat often struggles convulsively for a few seconds before it 

 can adjust its grip to its satisfaction ; but once in the pouch the 

 insect rarely escapes, and, when effectually secured, is brought 

 out and eaten openly. If the Bat can be induced to feed whilst 

 hanging head downwards, suspended by its toes, its actions can be 

 observed much more easily. Its tactics are then more efficacious, 

 as the tail is not pressed close to the belly, and the pouch is in 

 consequence held open, as it would be, of course, during flight. 



This habit, practised readily and frequently in captivity, is so 

 perfect an adaptation of means to an end that it must obtain with 

 equal frequency among Bats in a free state. These creatures, 



* In Bell's ' British Quadrupeds,' 2nd edit. p. 64, Daubenton's Bat is 

 described as thrusting its nose more or less downwards under its breast in 

 feeding; and in ' The Zoologist,' 1890, p. 99, a captive Pipistrelle is said to 

 have beaten moths against its breast to stun them. 



