Snail Kite (Rostrhamus sociabilis) Science Article 4
Snail Kites (Rostrhamus sociabilis sociabilis) observed along the lower Rio 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.
NOEL F. R. SNYDER AND HERBERT W. KALE, The Auk 100: 93-97. January 1983