Shorebirds feeding in mixed flocks in Fracasso Beach, Península Valdés, Argentina

D'AMICO, V. L.; BALA, L. O.; HERNÁNDEZ, M. A.

New Orleans, Louisiana

Conferencia; Third North American Ornithological Conference; 2002

We evaluated prey selection of Two-banded Plover and White-rumped Sandpiper forage  in mixed flocks at Fracasso Beach, Península Valdés, Argentina in relation to their feeding behaviour, by the use of bird flocks scans and faecal analysis. Both species have different techniques to capture their preys; Two-banded Plover use a visual strategic based on the pause-travel-pause, while White rumped Sandpiper use a tactile strategic. In addition, they have a similar bill-size. The prey species selected by both shorebirds have different burying depth and motility. These characteristics become them in susceptible or not for detected them visually or tactile by Two-banded Plover and Write rumped Sandpiper. Both birds species feed on the same area but they exploit at least partially different food niches.