After observing several nominate Lesser Black-backed Gulls (Larus fuscus fuscus) on Lake Tumba, Democratic Republic of the Congo, literature andmuseum studies were reviewed to compile observations of the species in the Congo basin. The Congo basin appears to be an important wintering area for these birds that are dispersed widely but thinly throughout the large network of rivers.Clearly, difficulties in performing fieldwork in the basin have, thus far, left this wintering area unrecognized.We suggest that the main wintering area for L. f. fuscus covers an area from the Rift Valley lakes westward into the Congo basin and, contrary to themainstream literature, only a small proportion of the population winter on the East African coast.