The food of three seabirds at Latham Island, Tanzania, with observations on foraging by masked boobies Sula dactylatra

Abstract

At Latham Island, Tanzania, in August 2004 and December 2005, flying fish (Exocoetidae) contributed 90% by mass of prey items regurgitated by masked boobies Sula dactylatra. The fish had a mean caudal length of 164mm. Two boobies generally foraged in deep water, away from the Tanzanian coastline, ranging up to 390km from the island. Maximum distances flown on trips exceeded 1 000km during breeding and approached 3 000km when not breeding. Some foraging trips exceeded six days. Swift terns Sterna bergii consumed small fish and mantis shrimps Natosquilla investigatoris. Mantis shrimps recovered from the colony were significantly larger than those stranded on the island's beach, suggesting that swift terns preferentially took larger animals. Sooty terns Sterna fuscata fed on small fish and squid.

Keywords: food, foraging, Latham Island, masked booby, sooty tern, Sterna bergii, Sterna fuscata, Sula dactylatra, swift tern

African Journal of Marine Science 2006, 28(1): 109–114