Comparative Feeding Ecology of Sea Birds of a Tropical Oceanic Island

In 1963 and 1964, 800 food samples, regurgitated or dropped by captured birds, were collected on Christmas Island (Pacific Ocean) from Phaethon rubricauda, Puffinus nativitatis, Pterodroma alba, Sterna fuscata, Anous stolidus, Gygis alba, Anous tenuirostris and Procelsterna cerulea....https://elischolar.library.yale.edu/peabody_museum_natural_history_bulletin/1023/thumbnail.jp

The Use of Food Samples from Sea Birds in the Study of Seasonal Variation in the Surface Fauna of Tropical Oceanic Areas

Many parts of the tropical oceans appear to be relatively seasonless, but, because of the difficulty of sampling mobile and patchily distributed animals and the cost of oceanographic investigations, few data are available on the extent of seasonal changes. By regularly collecting regurgitations from sea birds, and identifying and measuring the food items, seasonal data could be obtained on the availability, size classes, and perhaps reproductive cycles of the fish and squid characteristic of the surface layer of tropical seas. Flying fish (Exocoetidae), juvenile tunas (Scombridae), and squid of the family Ommastrephidae are especially easily obtainable. Experience gained during a recent study of the comparative feeding ecology of sea birds on Christmas Island (Pacific Ocean) makes it possible to assess the characteristics of bird species which affect their suitability for such study. Potentially useful species include terns (especially Sterna fuscata, Anous stolidas, A. tenuirostris, and Gygis alba) and boobies (especially Sula Sula). Samples could be obtained from several bird species in the same period, and a program could include sampling of inshore waters with the neuston net and making basic oceanographic observations. Investigations of this kind could be carried out economically on any of a large number of tropical oceanic islands