Yellow-billed stork and sacred ibis in Kabalega Falls National Park, east of Albert, Lake, Uganda

Yellow-billed storks make irregular migratory, partially migratory or nomadic movements within Africa to areas where changing water levels increase fish availability. Some populations are also largely sedentary. Breeding is seasonal and starts whenever food is most abundant according to local ecological conditions (e.g. when fish become concentrated in small wetlands or marshes), this may either be towards the end of the rains or during the dry season. The species breeds colonially, often with other species, usually in small groups of 10-20 pairs. It is a gregarious species but never aggregates into very large flocks, being more often observed in pairs or small flocks of up to 50 individuals. The species inhabits a variety of wetlands with shallow water 10-40 cm deep for feeding and sandbanks or trees for roosting. It frequents large swamps, the margins of rivers and lakes, lagoons, large marshes, small pools, flooded grassland, alkaline lakes, reservoirs, waterholes and rice-paddies. The species generally avoids areas of large-scale flooding and is rare in forested areas (although it may occur in wooded savanna). Its diet consists of small aquatic prey such as frogs, small fish, aquatic insects, worms, crustaceans and occasionally small mammals and birds. This photograph was taken when Eliot Elisofon was on assignment for American Broadcasting Company and traveled to Africa from June 1966 to early August 1966.