Mollusk Predation by Snail Kites in Colombia

Snail Kites (Rostrhamus sociabilis sociabilis) observed along the lower Río Magdalena in northern Colombia fed heavily on Pomacea chemnitzi but also took Marisa cornuarietis, a smaller species. The kites captured Pomacea preferentially over Marisa and had difficulties extracting Marisa from its shell. They also failed to extract some large specimens of P. chemnitzi. Failures with both species were apparently related to problems in removing opercula. These observations indicate that R. sociabilis can no longer be considered a strict specialist on Pomacea.