Continued development along the Atlantic Coast of North America and recent low American Oystercatcher population estimates have led to concern about the bird’s long-term survival. Human disturbance and predation are thought to be major causes of reproductive failure.

The American Oystercatcher was monitored on Cumberland Island National Seashore, during the 2003 and 2004 breeding seasons to determine to the effects of disturbance and predation on the reproductive success of American Oystercatchers. Ten to eleven breeding pairs established territories on the island and made 32 nesting attempts. Nine attempts were successful, fledging 13 chicks. Predation was the most common cause of nest failure, accounting for 15 nest failures. Egg predators included raccoons (Procyon lotor, 10), bobcats (Lynx rufus, 3) and fish crows (Corvus ossifragus, 1). One chick was depredated shortly after hatching, by a ghost crab (Ocypode quadrata, 1). Other causes of nest failure included tidal overwash (1), horse trampling (1), abandonment (2), and human destruction (1).

In addition, activity budget data were collected on all reproductively active pairs, as well as human related and natural disturbance affecting the birds. These data will be used this fall to establish disturbance frequency and duration, and to estimate tolerance of disturbance by adults during incubation and chick rearing.