ABSTRACT: This study confirms reports by fishermen of a large and predictable aggregation of whale sharks Rhincodon typus along the Belize Barrier Reef. Although whale sharks are rarely sighted at this location during most of the year, we countedas many as 25 whale sharks in a 50 m diameter area on 1 occasion and tagged 6 sharks during a 22 min period on another. The whale shark aggregation coincides seasonally and temporally with a multispecies reef-fish spawning aggregation at a reefpromontory, Gladden Spit, at sunset, during the full and last-quarter moon periods of April and May each year. We report here, for the first time, that whale sharks feed on the freshly released spawn of cubera snappers Lutjanus cyanopterus and dogsnappers L. jocu (Lutjanidae), and have documented the phenomenon with still and digital video photography of hundreds of feeding events. There is consensus locally that this remarkable interaction is in need of immediate protection fromoverfishing of snappers and unregulated tourism development. Our continued investigations are providing management recommendations for a new marine reserve at the site.