DISTURBANCES AT A ST.PETE BEACH BLACK SKIMMER COLONY

Black Skimmers are nocturnal colonial seabirds that breed in open beach habitat,  including high-traffic municipal beaches. The goal of this research was to quantify and determine the cause of disturbances to nesting Black Skimmers at St. Pete Beach in Pinellas County, Florida. Disturbances can potentially leave eggs or chicks vulnerable. We measured disturbances using camera traps at night and in-person surveys from late May -July, 2024. We quantified the number of times birds flushed (sudden, temporary exodus of the birds from their colony), the number of predation events, and acts of intraspecific aggression.  The cameras recorded 715 hours across 65 nights. In-person surveys were 3-5 hours/day for a total of 80 hours on 20 different days throughout the breeding season. Camera traps recorded 21 total flushes that occurred between dusk and dawn, 16 of which came from unknown causes, three caused by fireworks, one caused by a person walking in the colony, and one caused by a storm.  In-person surveys recorded 83 total disturbances: 23 of them being caused by anthropogenic reasons (fireworks, dogs, beach toys in the colony), 41 naturally caused (laughing gull and fish crows), 12 intraspecies disturbances, and 7 of them were from unknown causes.  Data from the cameras demonstrated that there were relatively few disturbances at night, although the causes were mostly inconclusive. In-person surveys demonstrated there were more disturbances during daylight and that potential predators caused most of the disturbances.

For more information: rkshedden@eckerd.edu or achernandez@eckerd.edu