The Breeding Behaviour of the Common Frog, Rana temporaria temporaria Linn., and of the Common Toad, Bufo bufo bufo Linn.
- 1By tagging individual frogs in a pond it was found that the males, after mating once, remained behind in the pond with the other males, and often mated several times in one season. Other males did not secure mates at all. Pairs remained in amplexus under natural conditions less than twenty-four hours.
- 2The recognition of the female by the male depends primarily on the rough granules of her skin, which are developed during the breeding season, a different method of sex recognition from any hitherto described. She is retained after seizure because she remains silent and has a stout figure. When she lays her eggs she is released by the automatic cessation of the impulse to grip, resulting from her diminished size, aided by the use of her voice.
- 3The female assists the expulsion of her eggs by pressing her hands on her abdomen and forcing them out.
- 4The sperm-emission stimulus is merely the contact of the eggs with the symphysis pubis region of the male.
- 5The males struggle for the possession of the females by using their feet to push away or force off their opponents, especially by hooking their toes under the encircling arms of the other frog. This appears to be the only point at which the nuptial pads perform a useful function.