SATELLITE TELEMETRY OF GREAT FRIGATEBIRDS FREGATA MINOR REARING CHICKS ON TERN ISLAND, NORTH CENTRAL PACIFIC OCEAN

摘要

The Papahanaumokuakea Marine National Monument in the Northwestern Hawaiian Islands protects breeding habitat for many migratory animals. We used satellite telemetry to describe the areas in which a mobile top predator, the Great Frigatebird Fregata minor, traveled on foraging trips during the early chick-rearing period from a breeding colony on Tern Island, French Frigate Shoals. Identification of potential foraging events, indicated by a reduction in transit rate, allowed us to assess whether wide-ranging marine species such as Great Frigatebirds remain inside the protective boundaries of the Monument while brooding young chicks. Four of 11 foraging trips extended outside of the boundaries of the Monument. These movements may represent the shortest foraging distances that Great Frigatebirds travel from the colony because adults need to provision young chicks frequently. We also tracked one male that abandoned its nest on a journey to the southwest of Tern Island. This bird was tracked for 16 daysbefore the transmitter's battery expired, and the last transmitted position was nearly 1100 km from Tern Island. These tracks, the first reports of frigatebird telemetry in the Pacific Ocean, provide information about the foraging behaviors of a top predator during a critical life-history stage—data that will complement tracking data of other species and aid in future conservation and management decisions concerning the Monument and surrounding waters of the Northwestern Hawaiian Islands.