Creature record / 1932
1932. The British Cameroons. Ivan T. Sanderson and Gerald Russell were paddling separate canoes across the Mamfe Pool of the Mainyu River. Cliff-like banks slid past, pocked with deep caves. Some were partly flooded. Then a roar came out of one of them. The current dragged both canoes toward the cave mouth. The water foamed. Something enormous rose out of the river. A shiny black head, shaped like a seal but flattened, about the size of a full-grown hippopotamus. It went back under almost at once. The two men did not stay. Their guides had a name for the animal. M'koo m'bemboo. Sanderson first mentioned it in a letter in 1958.
The trip is described as part of the Percy Sladen Expedition to West Africa. Ivan T. Sanderson, a young zoologist born in Edinburgh, was collecting mammals in the Mamfe Division of the British Cameroons. Beside him was Gerald Russell, an American naturalist and animal collector. Five years later Russell would help capture a live giant panda.