Fishes: Aphyosemion Bivittatum

Sunday, 22 July 2012

Aphyosemion Bivittatum

Aphyosemion Bivittatum is a small lake in the volcanic chain in the Southwest Region of Cameroon. It is a volcanic lake with a diameter of about 1.2 km (0.75 mi).There is a small island in the middle, which is densely inhabited by the Barombi, a tribe of fishers. The Tung Nsuia and Tung Nsuria streams, each about 1–2 m (3 ft 3 in–6 ft 7 in) wide and 0.3 m (1 ft 0 in) deep near their mouth, are the only inflows into the lake, and they dry out in dry season.Lake Barombi Koto often appears green-brown because it is rich in phytoplankton.Invertebrates, turtles and the aquatic frog Xenopus tropicalis are common in the lake,which is also an important sanctuary for birds.Seven fish species are known from the lake, including Barbus callipterus and a Clarias catfish, while the remaining all are cichlids: Chromidotilapia guentheri, Hemichromis fasciatus, Sarotherodon galilaeus, Tilapia kottae and T. mariae. Of these, C. guentheri is represented by the endemic subspecies loennbergi, while T. kottae is entirely endemic to this lake and the smaller Lake Mboandong. Both endemics are threatened by pollution and sedimentation from human activities, and "turning" of the lake's water because of deforestation of the surroundings (this may allow more wind, and the lake is stratified with oxygen-poor lower levels).They are potentially also threatened by large emissions of carbon dioxide from the lake's bottom.