Micrurus frontalis pyrrhocryptus (coral snake). Predation

PUETA MARIANA

HERPETOLOGICAL REVIEW

Society for the Study of Amphibians and Reptiles

Lugar: Salt Lake City, USA; Año: 2002 vol. 33 p. 215 - 215

0018-084X

Observations of predation on Micrurus by birds are scarce (Pough 1988. In Gans and Huey (eds.), Biology of the Reptilia, 16:153-234. Alan R. Liss, Inc., New York; Roze 1926. Coral snakes of the Americas: biology, identification and venoms. Malabar, Fla.: Krieger, 328pp). Here I report predation by Cariama cristata (red-legged chuña or seriema, Aves: Cariamidae) on Micrurus f. pyrrhocryptus. The event occurred on April 10, 2000 at 1500 h in the Graciela Ranch (S 29º 40,945- W 64º 02,443), Departamento Sobremonte in the northwest of the Province of Cordoba, Argentina. The adult snake (ca. total length 30 cm) was first seen by the semi-tame, allowing close observation, but wild bird from a distance of ca. 6 m. It ran rapidly toward the snake and captured it by the head. I followed and observed the encounter from a distance of a meter or less. First, the bird crushed the head with repeated closures of its beak, then still holding it by the head, it lifted the coral snake into the air and rapidly swung it downwards onto the ground. The action was similar to that used by roadrunners ("centrifugal-slam" technique; Sherbrooke 1990. Wilson Bulletin 102:171-174). Possibly this was to ensure that the snake was dead. Then it dropped the snake onto the ground and waited 15-30 sec. before picking it up again in its beak, near the head. The bird then proceeded to reposition its thin-bodied prey in its beak several times before beginning to ingest it, a section posterior to the head entering first and leaving two portions extending from its mouth. The slow swallowing (encompassing at least 2 min.) proceeded until first the head end was completely engulfed and then the tail end. Snakes are uncommon prey items of Cariama cristata (Sick 1993. Birds in Brazil: A Natural History, pp. 217-219. Princeton University Press, New Jersey). This observation suggests that the red-legged chuña or seriema does not have an innate fear response to coral-snake colors and pattern, as has been reported in other birds (Smith 1975. Science 187:757-760; Smith 1977. Nature 265:535-536), and that coral snakes, inspite of their venom, may not have an effective defense against the bird`s attack.