Avian reproduction is a process that requires extensive energetic input by parents, particularly in pelagic seabirds. Parental infanticide has rarely been reported in pelagic seabirds, and its frequency among taxa is therefore difficult to determine. Using data from remote cameras, two cases of probable parental infanticide in Red-billed Tropicbirds Phaethon aethereus were captured on Sint Eustatius in the 2021–2022 breeding season. Both cases are presented with images collected from remote cameras as evidence. While appearing counterproductive, parental infanticide may provide an alternative reproduction strategy that favors lifetime reproductive success over short term success.
AbstractUrbanization has introduced novel materials for nesting birds, including anthropogenic debris that may be dangerous to adults and nestlings (e.g., entanglement or ingestion leading to injury or mortality). We present two observations of incorporation of man-made materials into passerine nests on St. Eustatius, Caribbean Netherlands. This is the first publication of such observations for St. Eustatius, and addresses a gap in literature that acknowledges the use of anthropogenic litter by landbirds in the wider Caribbean.
Red-billed Tropicbirds breeding on Pilot Hill on the island of Sint Eustatius have been exhibiting an average survival rate of between 30-40%. The influence of nest cavity attributes, environmental covariates, and parent behavior on Red-billed Tropicbird survival were evaluated through nest surveys and camera trap data. Daily survival rate was calculated as a function of selected covariates. Time spent away from the nest by parents and minimum temperature were the most influential factors. Nest attributes and temperature variables did not correlate to survival.