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27-416: Malapterurus Paradoxoglanis Electric catfish or Malapteruridae is a family of catfishes (order Siluriformes). This family includes two genera , Malapterurus and Paradoxoglanis , with 21 species . Several species of this family have the ability to generate electricity , delivering a shock of up to 350 volts from its electric organ . Electric catfish are found in tropical Africa and

54-738: A tingle to humans. Malapterurus See text. Malapterurus is a genus of catfishes ( order Siluriformes) of the electric catfish family (Malapteruridae). It includes 18 species . The genus Malapterurus is found throughout western and central tropical Africa and the Nile River . They occur in all major freshwater systems including the Buzi , Niger , Ogooué , Omo , Sanaga , Sabi-Lundi , Senegal , Shari , Congo , and Zambezi River basins, as well as Lakes Albert , Chad , Kainji , Tanganyika , and Turkana . Malapterurus have an elongate and cylindrical body that gives them

81-456: Is a voracious piscivore . It uses its electrical discharges to stun prey. It is an opportunistic feeder and will feed on any readily available prey in the habitat. These fish are slow-moving, deliberate feeders with infrequent, heavy meals. Breeding pairs of M. electricus nest in holes about 3  metres (10  ft ) in length excavated in clay banks in water 1–3 m (3.3–9.8 ft) deep. The electrical discharge of M. electricus

108-523: Is derived from anterior body musculature and lines the body cavity. Electric catfish do not have dorsal fins or fin spines. They have three pairs of barbels (the nasal pair is absent). The swim bladder has elongate posterior chambers, two chambers in Malapterurus and three in Paradoxoglanis . Malapterurus have been conditioned by means of reward to discharge on signal. As reported in

135-402: Is not known to be fatal to humans. M. electricus is eaten as food in certain parts of Africa. Along the shores of Lake Kainji , smoked electric catfish is a popular delicacy. M. electricus is also sometimes encountered as an aquarium fish. There are currently 18 recognized species in this genus: Lake Albert (Africa) Lake Albert is located on the border between Uganda and

162-661: Is relatively stable throughout, typically around 27–29 °C (81–84 °F), and even its deeper sections contain oxygen. The water has a pH of around or just below 9 and an electric conductivity of around 720–780 μS/cm. These are both very high for a freshwater lake but nevertheless lower than Lake Edward. Lake Albert is home to many aquatic and semi-aquatic animals like hippopotamuses , Uganda kob antelopes, Nile crocodiles , Nile monitors , African softshell turtles , Central African mud turtles , Williams' mud turtles , various semi-aquatic snakes and various frogs. Water birds are numerous and include pelicans , herons and

189-580: The Alur as well as other peoples who have inhabited the region for centuries before the colonial age . This name means ‘locust killer’, from omwita ‘killer’ and enzige ‘locusts’ in the Runyoro language, and 'The Lake that has defeated the locusts' in the Alur language, from Nam , 'Lake', Ovoyo , 'has defeated', Bonyo , 'Locusts'. This is due to a local legend that tells how a plague of locusts had destroyed

216-653: The Democratic Republic of the Congo . It is the northernmost of the chain of lakes in the Albertine Rift , the western branch of the East African Rift . It is about 160 kilometres (99 mi) long and 30 kilometres (19 mi) across at its widest, with a maximum depth of 51 metres (167 ft), and a surface elevation of 619 metres (2,031 ft) above sea level. Lake Albert is part of

243-592: The Mountain Nile when its course enters South Sudan . At the southern end of the lake, where the Semliki comes in, there are swamps . The Rwenzori Mountains are to the south of the lake and to the northwest, the Blue Mountains . The few settlements along the shore include Butiaba and Pakwach . Unlike the very deep Lake Malawi , Lake Tanganyika and Lake Kivu , Lake Albert's water temperature

270-643: The New York Times on April 2, 1967, researcher Dr. Frank J. Mandriota of City College of New York conditioned a M. electricus to discharge on a light signal for a reward of live worms delivered automatically. This is a first in conditioning that modified neither glandular nor muscular responses. M. electricus can grow as large as 122 centimetres (48 in) TL and 20 kilograms (44 pounds). Malapterurus species are generally found among rocks or roots in turbid or black waters with low visibility. They favor sluggish or standing water. M. electricus

297-525: The New York Times , April 2, 1967, a researcher, Dr. Frank J. Mandriota of City College, New York, conditioned an M. electricus to discharge on a light signal for a reward of live worms delivered automatically. This is the first conditioning that modified neither glandular nor muscular responses. The largest can grow to about 1.2 meters (3 ft) and 20 kg (44 lb). Most Malapterurus and all Paradoxoglanis species are much smaller, reaching less than 30 cm (1 ft) long. The electric catfish of

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324-548: The Nile River . Electric catfish are usually nocturnal and carnivorous. Some species feed primarily on other fish, incapacitating their prey with electric discharges, but others are generalist bottom foragers, feeding on things like invertebrates, fish eggs, and detritus . The largest can grow to about 1.2 meters (3 ft) long, but most species are far smaller. The Malapteruridae are the only group of catfish with well-developed electrogenic organs; however, electroreceptive systems are widespread in catfishes. The electrogenic organ

351-588: The Nile tilapia , Niger barb , Albert lates , electric catfish and giraffe catfish that are caught by standard fishing methods, and the small Brycinus nurse and Engraulicypris bredoi that mainly are caught by light fishing . As much as 30% of the fish production in Uganda is from Lake Albert. Lake Albert has fewer endemics than the other African Great Lakes . Although the Albert Nile–the section of

378-535: The Lake Albert basin, with estimates that the multi-billion barrel field will prove to be the largest onshore field found in sub-Saharan Africa for more than twenty years. In March 2014, a boat carrying Congolese refugees capsized in Lake Albert , killing more than 250 people. On 26 December 2016, a boat carrying 45 members and fans of a local village football team capsized in Lake Albert killing at least 30 people. On 24 December 2020, thirty people died when

405-680: The Nile ( H. loati and Pseudocrenilabrus multicolor ). In comparison, most of the more than 60 haplochromines in Lake Edward–George and most of the roughly 600 haplochromines in Lake Victoria–Kyoga are endemic. The only other endemic fish species in Lake Albert are the small cyprinid Engraulicypris bredoi and the endangered Albert lates. Lake Albert is still known as Mwitanzige by the Banyoro and Batooro , and Nam Ovoyo Bonyo by

432-582: The Nile that leaves Lake Albert—has several rapids in the Nimule region, these have not effectively isolated the lake from the main Nile sections. In contrast, Lake Edward (and ultimately Lake George ) is effectively isolated from Lake Albert by the rapids on the Semliki River, while Lake Kyoga (and ultimately Lake Victoria) is effectively isolated from Lake Albert by the Murchison Falls on

459-490: The Nile was well known to the ancient Egyptians . The Egyptians reputedly used the electric shock from them when treating arthritis pain. They would use only smaller fish, as a large fish may generate an electric shock from 300 to 400 volts. The Egyptians depicted the fish in their mural paintings and elsewhere; the first known depiction of an electric catfish is on a slate palette of the predynastic Egyptian ruler Narmer about 3100 BC . An account of its electric properties

486-465: The Victoria Nile. As a consequence, most of Lake Albert's fish are widespread riverine species also found in the main Nile sections. There are few haplochromine cichlids; a group that is very diverse in other Rift Valley lakes. Of the six haplochromines in Lake Albert, four are endemic ( Haplochromis albertianus , H. avium , H. bullatus and H. mahagiensis ) and two are also found in

513-406: The back and sides, fading to an off white or cream color on the ventral surfaces of the head and body. There are irregular black spots or blotches randomly distributed on the sides of the body. The posterior half of the caudal peduncle usually has a dark brown or black vertical bar and a cream vertical bar immediately before it. The edges of the anal and caudal fins have a cream margin, and the base of

540-420: The caudal fin has a cream region and a dark brown crescent-shaped band immediately after it. The electrogenic organ is derived from anterior body musculature and lines the body cavity. A fish that is 50 centimetres (19 in) in length can discharge up to 350  V . M. electricus is one of the few electric species that have been conditioned by means of reward to discharge on signal. As reported in

567-654: The complicated system of the upper Nile . Its main sources are the White Nile , ultimately coming from Lake Victoria to the southeast, and the Semliki River , which issues from Lake Edward to the southwest. The water of the Victoria Nile is much less saline than that of Lake Albert. The lake's outlet, at its northernmost tip, is the Albert Nile section of the White Nile. The river later becomes known as

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594-456: The crops of the people who were living on the eastern shore of the lake, but when they tried to cross to the other side they never got there. In 1864, the explorers Samuel Baker and Flóra von Sass found the lake and renamed it after the recently deceased Prince Albert , consort of Queen Victoria . In the 20th century, Zairian President Mobutu Sese Seko temporarily named the lake after himself. European colonialists operated shipping on

621-513: The general appearance of a sausage . The eyes are small, the lips are rather thick, and the snout is rounded with widely separated nostrils. The gill openings are narrow and restricted to the sides. Malapterurus species have three pairs of barbels, and lack a dorsal fin . The pectoral , pelvic , and caudal fins are rounded. The swimbladder has two elongate posterior chambers. Species in Malapterurus are generally grayish-brown on

648-546: The lake. The British planned shipping on Lake Albert as part of a network of railway, river steamer and lake steamer services linking British interests in Egypt, east Africa and southern Africa. The John I. Thornycroft & Company shipyard at Woolston, Hampshire built the cargo and passenger ship SS  Robert Coryndon for this purpose in 1930. She was named after the British Army officer Robert Thorne Coryndon, who

675-461: The rare shoebill . There are 55 fish species in Lake Albert. Except for Nile crocodiles, the largest predator in the lake is the Nile perch (native; unlike in other Rift Valley lakes where introduced and invasive ). Other large predatory fish include the elongate tigerfish , African tigerfish , marbled lungfish , cornish jack , Bagrus docmak , African sharptooth catfish and vundu catfish. In addition, there are important fisheries for

702-418: Was given by an Arab physician Abd al-Latif al-Baghdadi of the 12th century; then as now, the fish was known by the suggestive name of الرعد el raad , which means "thunder". The shock of these catfish is used to stun prey and in defense. It is not known to be fatal to humans, but large electric catfish can stun an adult person. In small electric catfish, the generated current is far less and only feels like

729-400: Was governor of Uganda 1918–22. Winston Churchill described the ship as "the best library afloat" and Ernest Hemingway called her "magnificence on water" . She either was scuttled in 1962 or sank in 1964. She remains unsalvaged and partly submerged in the lake at Butyaba landing site. These can still be seen to date. Heritage Oil and Tullow Oil have announced major oil finds in

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