The Black Noddy (Anous minutus) and the Brown Noddy (A. stolidus) occur sympatrically in the Southern Lagoon of New Caledonia, breeding on islets located at the edge of a wide, productive coral-reef lagoon next to oceanic waters enriched by a seasonal upwelling. The diets of the two species were determined from regurgitations from birds nesting at Kouaré Islet during two consecutive breeding seasons (2002/2003 and 2003/2004), and compared. The average prey load in the Brown Noddy was heavier than that of the Black Noddy, as expected from its larger body size and from a predicted longer foraging distance. Fish prey dominated the diet of both species (100% and 81.8% biomass in Black and Brown Noddies, respectively), the remainder consisting of squid. Black Noddy ate small pelagic fishes inhabiting the reef and the lagoon, mainly round herrings (Spratelloides spp.), while Brown Noddy mainly preyed on offshore species including buccaneer anchovy (Encrasicholina punctifer) and larger pelagic fishes (Exocoetidae), and squid. The segregation in diet between Black and Brown Noddies in New Caledonia thus indicated spatial segregation in foraging zones, i.e. inshore vs. offshore, respectively, which was more pronounced than previously reported for other sites where the two species co-occur.