African Longfin Eel

This taxon is one of a number of demersal species in the Zambezi River system of southern Africa. Demersal river fish are found at the river bottom, feeding on benthos and zooplankton Nutrient levels in the Zambezi River are relatively low, especially in the upper Zambezi; in that reach, above Victoria Falls, most of the catchment drains Kalahari sands, whose nutrient levels are inherently low due to their aeolian formation; moreover, agricultural fertilizer addition throughout the Zambezi watershed is low, due to the shortage of capital available to farmers of this region. Nitrate levels (as nitrogen) in the upper Zambezi are typically in the range of .01 to .03 milligrams per liter. Correspondingly electrical conductivity of the upper Zambezi is on the order of 75 micro-S per centimeter, due to the paucity of ion content. From the Luangwa River downstream nitrate levels elevate to .10 to .18 milligrams per liter, and electrical conductivity rises to a range of two to four times the upper Zambezi levels. Not surprisingly, pH, calcium ion concentration, bicarbonate and electrical conductivity are all higher in portions of the catchment where limestone soils predominate compared to granite. There are a total of 190 fish species present in the Zambezi River, including eel and shark taxa. The largest native demersal species present are the 117 centimeter (cm) long tiger fish (Hydrocynus vittatus), the 175 cm African mottled eel (Anguilla bengalensis labiata), the 120 cm Indonesian shortfin eel (Anguilla bicolor bicolor), the 200 cm Giant mottled eel (Anguilla marmorata), the 150 cm African longfin eel (Anguilla mossambica), the 183 cm Sampa (Heterobranchus longifilis), the 150 cm Cornish jack (Mormyrops anguilloides) and the 700 cm largetooth sawfish (Pristis microdon).

Olive to greyish black dorsally, lighter ventrally (Ref. 3971). Caudal fin confluent with dorsal and anal.

Aeromonosis. Bacterial diseases

Anguillicola Infestation 2. Parasitic infestations (protozoa, worms, etc.)

Mugilicola Infestation. Parasitic infestations (protozoa, worms, etc.)

Pseudomonas infection 2. Bacterial diseases

Catadromous. Migrating from freshwater to the sea to spawn, e.g., European eels. Subdivision of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.

Dorsal spines (total): 0; Analspines: 0

Inhabits both quiet and fast flowing water. Elvers ascend rivers mainly at night and overcome waterfalls and walls of dams with great determination. Adults usually sedentary. Carnivorous, eats dead or living prey but especially fish and crabs.

Migratory species, which breeds in the ocean (Ref. 52331). Inhabits both quiet and fast flowing water (Ref. 13337). Elvers ascend rivers mainly at night and overcome waterfalls and walls of dams with great determination. Adults usually sedentary. Females can attain 120 cm SL and are generally longer and heavier than males (Ref. 48660). Carnivorous, eats dead or living prey but especially fish and crabs. After feeding in fresh water for ten years or more, adults assume a silver breeding dress, the eyes become enlarged and they return to sea to breed. Considered to breed east of Madagascar, but thought to move south of that island on its way to the Mozambique coast and South African rivers (Ref. 13337). Flesh fatty but highly esteemed as smoked or jellied eel (Ref. 5214). Caught with various types of nets (Ref. 4967).

fisheries: commercial; aquaculture: commercial; gamefish: yes

The African longfin eel (Anguilla mossambica), also known simply as the longfin eel, is an eel in the family Anguillidae. It was described by Wilhelm Peters in 1852, originally under the genus Muraena. It is a tropical eel known from freshwaters in southern Kenya, Cape Agulhas, Madagascar, and New Caledonia. The eels spend most of their lives in freshwaters far inland, but migrate to the Western Indian Ocean to breed. Males can reach a maximum total length of 150 centimetres; females can reach a maximum standard length of 120 centimetres and a maximum weight of 5,000 grams. The eels can live for about 20 years. Juveniles and adults are known to feed off of carcasses, crabs, and bony fish.

Carnivorous, eats dead or living prey but esp. fish and crabs. Elvers ascend rivers mainly at night and overcome waterfalls and walls of dams with great determination. Adults usually sedentary. After feeding in fresh water for ten years or more, adults assume a silver breeding dress, the eyes become enlarged and they return to sea to breed. Flesh fatty but highly esteemed as smoked or jellied eel (Ref. 5214). Caught with various types of nets (Ref. 4967).