Hydrocynus goliath | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Characiformes |
Family: | Alestidae |
Genus: | Hydrocynus |
Species: | H. goliath |
Binomial name | |
Hydrocynus goliath (Boulenger, 1898) | |
Catchment area for Hydrocynus goliath | |
Synonyms [2] | |
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Hydrocynus goliath, also known as the goliath tigerfish, giant tigerfish, or mbenga, is a very large African predatory freshwater fish of the family Alestidae.
Goliath tigerfish(Hydrocynus goliath) is one of five recognized African species of the Hydrocynus genus and is found in the Congo River Basin (including Lualaba River and Lake Upemba), and Lake Tanganyika . [3] [4] The type locality is the city of Mbandaka in the Main Congo, where it was discovered in 1898 by French explorer Boulenger. [5] They are typically found in highly oxygenated fast-flowing waters such as those found in deep river channels and open lakes, making them strong swimmers able to capture prey even in turbulent waters. [6]
A 2011 study which reconstructs the phylogenetic history of genus Hydrocynus using comparisons of a protein-coding gene called cytochrome b, revealed several mtDNA clades in this region, suggesting a higher tigerfish species richness than traditionally recognized. The study’s analyses indicate that populations of H. goliath may have been prevented from upstream dispersal in the geologic past by knickpoints, or sharp changes in the channel bed slope, in the Luvua river. This prevention of upstream dispersal would restrict H. goliath to the Congo River Basin as reflected in the modern range of the species. [7] Four additional species ( H. vittatus and three unknown species) appear to be present in this Basin, while two (H. vittatus and an unknown species) appear to be present in Lake Tanganyika. [7]
Based on the study’s sequence comparisons, H. goliath possesses low nucleotide diversity, suggesting that existing populations originate from a historically small effective population which underwent rapid population growth at some point in the past. Additionally, a high haplotype diversity value indicates that its expansion may have undergone a more recent expansion in its population range and size. [7]
The goliath tigerfish has a characteristic silvery gray dorsum and flanks, with a tunniform body plan similar to that of tuna, featuring black adipose fins. The goliath tigerfish is described as the "Monster Fish of the Congo" by a 2008 documentary by National Geographic, a reflection of its monster-like qualities and of its perception by local people and hunters. This large-toothed, highly predatory fish grows to an average length of 1.5 m (4.9 ft) and a weight of 50 kg (110 lb). [8] The largest recorded specimen weighed 70 kg (154 lb), [4] and they can reach a maximum recorded length of about {{cvt|2|m|ft|1), making them the largest of the tigerfish of genus Hydrocynus. [9]
In addition to being the largest in body size of their genus, they also have incredibly large conical teeth. Due to their predatory nature, they possess well-developed pharyngeal teeth similar to those of sharks and piranhas. [9] Their teeth are spaced out along the jaw and shaped like daggers in order to facilitate biting pieces out of prey fish or tearing prey into smaller pieces for digestion. The premaxilla holds six to seven teeth while the dentary or lower jaw holds five, for a total of 12 to 20 upper teeth plus 8 to 14 lower teeth. Its teeth fit into distinct grooves along its jaws, interlocking together with the smallest teeth are found at the very back of the jaws and. In each jaw quadrant, all teeth are replaced at the same time over the course of about five days. [9] On average each of its teeth can grow up to 2.5 cm (1 in), [4] according to biologist and television presenter Jeremy Wade, [8] which is comparable to the tooth size of a Great White shark. These massive jaws and teeth are what sets this species apart from all other tigerfish of the genus Hydrocynus and make for easy identification, especially given its endemism to the Congo Basin.
Despite being mostly solitary hunters, female goliath tigerfish migrate together and breed near each other on riverbanks or lakeshores. Thousands of eggs are laid among thick vegetation to protect the eggs and the young from predators, given that goliath tigerfish are not attentive parents. Infant fish feed on animal plankton during their larval stage before transitioning to small fish and eventually an adult diet of larger fish. Juvenile fish grow quite slowly, averaging four to six inches of growth per year. It can take up to ten years for a juvenile tigerfish to reach its full adult size. [5]
Hydrocynus goliath is a piscivore, feeding on any fish it can overpower, including smaller members of the same species. Their huge, powerful, rigid teeth make them one of the most ferocious predators of the Congo basin, dangerous for the smaller fish they prey on as well as for the hunters who attempt to capture them for sport and for food.[ citation needed ] They have been known to attack larger animals, taking "chunks" out of large fish, crocodiles, humans, or even each other in desperate times.
When hunting, this fish uses the calmer eddies of the rapids to ambush its prey, using its keen sight to detect prey. When a target is noticed, the fish accelerates to chase it down. The Nile crocodile is the only known natural predator of mature goliath tigerfish. Humans are also considered predators as they hunt tigerfish for food and sport.
A number of incidents have been reported in the Congo of this fish attacking humans. [4] [5] This reputation, combined with its strength, has earned it an almost mythical status among anglers, and it has been called the "greatest freshwater gamefish in the world". [5] Hunters and fisherfolk in the Congo River Basin often spend entire days battling these huge fish. Its enormous size and shearing teeth make it powerful and difficult to capture, earning it the title of one of the world’s greatest sports fishing challenges in sports fishing magazines. [10]
Throughout the Congo, the goliath tigerfish is known by its native Swahilli name "mbenga," which translates to "dangerous fish." Native people believe the fish to be an evil spirit which is to be avoided, especially at the start of a journey on water.
The goliath tigerfish is one of many fishes that plays an important role in the diet and economy of African countries. In the Central African Republic, a study investigates how to manage infestations of Dermestes beetles in the dried fishes which are crucial for supplying protein to Central Africans.[ citation needed ] The study shows that tigerfish are susceptible to the development of Dermestes, with considerable losses to the fish product as the pest eats through the skin, lays larvae, and contaminates the fish as a food source. Infestation of dried fishes comes with financial loss for Central and South African economies, with an estimated annual loss of £750,000 ($1,000,000 USD) in South Africa specifically. [11] Dried fish carrying the Dermestes and their larvae can go on to damage timber, cotton, linen, and other materials. Though methods of prevention through traditional management of dried fishes were investigated, the development of the Dermestes subspecies found in dried tigerfish has not yet been effectively reduced.
In addition to pests, bacteria is commonly found in dried tigerfish. To combat this, many sellers use either traditional methods or toxic pesticides that increase the shelf life, the latter of which has health implications for Africans eating the fish. Researchers recommend further study regarding the specific bacterial concentrations at each stage of the processing of dried fish, as well as training for the sellers regarding safer handling practices.
The goliath tigerfish is sometimes kept as a display fish in home aquarium setups, however due to their enormous size, often times reaching over 84 in (2,100 mm) in length they are not suitable all but the most experienced fishkeepers with the ability to house them. The recommended size of such a tank setup would be around 4,000 U.S Gallons. They are predatory fish with razor sharp teeth and are hostile to most other inhabitants; it's recommended to keep them alone or with larger and more boisterous species that can hold their own against the Tiger fish. When feeding, this massive fish will only feed on live prey, making feeding them difficult. [12]
The current conservation status of the goliath tigerfish is unknown, but it is listed as "least concern" according to the IUCN Red List’s 2010 assessment. [1]
The goliath frog, otherwise known commonly as the giant slippery frog and the goliath bullfrog, is a species of frog in the family Conrauidae. The Goliath frog is the largest living frog. Specimens can reach up to about 35 centimetres (14 in) in snout–vent length and 3.3 kilograms (7.3 lb) in weight. This species has a relatively small habitat range in Cameroon and Equatorial Guinea. Its numbers are dwindling due to habitat destruction, collection for food, and the pet trade.
Polypterus senegalus, commonly known as the Senegal bichir, gray bichir or Cuvier's bichir, is an African species of ray-finned fish in the bichir family, Polypteridae. It is a typical example of polypterid fishes, as most of its defining physical features are common across the genus, such as its ancient, lungfish- or arowana-like appearance, the ability to breathe atmospheric oxygen, and its armor-like scales. These factors have influenced the species' popularity in captivity, and it is commonly kept by aquarists and other hobbyists.
Tigerfish can refer to fish from various families, and derives from official and colloquial associations of these with the tiger. However, the primary species designated by the name "tigerfish" are African and belong to the family Alestidae.
The African fish eagle or the African sea eagle is a large species of eagle found throughout sub-Saharan Africa wherever large bodies of open water with an abundant food supply occur. It is the national bird of Malawi, Namibia, Zambia, and Zimbabwe. As a result of its large range, it is known in many languages. Examples of names include: Vis Arend in Afrikaans, nkwazi in Chewa, aigle pêcheur in French, hungwe in Shona, inkwazi in isiZulu, and ntšhu in Northern Sotho. This species may resemble the bald eagle in appearance; though related, the two species occur on different continents, with the bald eagle being resident in North America.
Mbenga may refer to:
A piscivore is a carnivorous animal that primarily eats fish. The name piscivore is derived from Latin piscis 'fish' and vorō 'to devour'. Piscivore is equivalent to the Greek-derived word ichthyophage, both of which mean "fish eater". Fish were the diet of early tetrapod evolution ; insectivory came next; then in time, the more terrestrially adapted reptiles and synapsids evolved herbivory.
Hepsetus odoe, the African pike characin, is a predatory freshwater characin belonging to the family Hepsetidae. It was formerly considered that there was a single species of Hepsetus pike characin but recent studies have led to the species being split and Hepsetus odoesensu stricto is the west African representative of the group.
Salminus brasiliensis, also known as the golden dorado, dorado, river tiger, dourado, or jaw characin is a large, predatory characiform freshwater fish found in central and east-central South America. Despite having Salminus in its name, the dorado is not related to any species of salmon, nor to the saltwater fish also called dorado. It is very popular among recreational anglers and supports large commercial fisheries.
Hydrocynus is a genus of characin fish in the family Alestidae commonly called "tigerfish," native to Africa. The genus name is derived from Ancient Greek ὕδωρ ("water") + κύων ("dog"). The genus contains five species, all commonly known as "African tigerfish" for their fierce predatory behaviour and other characteristics that make them excellent game fish. Hydrocynus are normally piscivorous, but H. vittatus is proven to prey on birds in flight.
The Lake Tanganyika sardine is a species of freshwater ray-finned fish in the family Dorosomatidae which was endemic to Lake Tanganyika but which has now been introduced to other lakes in Africa as a food source. It is one of two species within the genus Limnothrissa, the other being the Lake Mweru endemic, L. strappersi. This species and the Lake Tanganyika sprat are known collectively as kapenta.
Serranochromis is a genus of relatively large, robust cichlids from freshwater habitats in mainland Southern Africa, ranging as far north as DR Congo and Tanzania, with the highest species richness in the upper Zambezi, Okavango and Congo basins. They are typically known as largemouths or, especially among fishers, breams. Serranochromis are mostly piscivores and they are important in local fisheries.
Livyatan is an extinct genus of macroraptorial sperm whale containing one known species: L. melvillei. The genus name was inspired by the biblical sea monster Leviathan, and the species name by Herman Melville, the author of the famous novel Moby-Dick about a white bull sperm whale. Herman Melville often referred to whales as "Leviathans" in his book. It is mainly known from the Pisco Formation of Peru during the Tortonian stage of the Miocene epoch, about 9.9–8.9 million years ago (mya); however, finds of isolated teeth from other locations such as Chile, Argentina, the United States (California), South Africa and Australia imply that either it or a close relative survived into the Pliocene, around 5 mya, and may have had a global presence. It was a member of a group of macroraptorial sperm whales and was probably an apex predator, preying on whales, seals and so forth. Characteristically of raptorial sperm whales, Livyatan had functional, enamel-coated teeth on the upper and lower jaws, as well as several features suitable for hunting large prey.
Hydrocynus vittatus, the African tigerfish, tiervis or ngwesh is a predatory freshwater fish distributed throughout much of Africa. This fish is generally a piscivore but it has been observed leaping out of the water and catching barn swallows in flight.
Hydrocynus tanzaniae, the blue tigerfish, is a large African predatory freshwater fish.
Hydrocynus brevis, also known as the tigerfish, Nile tigerfish or Sahelian tigerfish, is a predatory freshwater fish distributed throughout Africa.
There are two major sources of fish in Uganda; one is from aquaculture, the other from fishing in rivers and lakes. Different types of fish flourish in different water sources. The waters of Uganda contain an impressive array of fish species—over 90 in all. This count does not include the Haplochromis complex, which itself is made up of more than 200 species.
Hepsetus cuvieri, the African pike, Southern African pike or Kafue pike characin, is a predatory species of freshwater ray-finned fish belonging to the monotypic family Hepsetidae, the African pike characins. This fish is found in southern Africa. It was formerly classified within the single widespread African species Hepsetus odoe but this has now been split into a number of valid species.
Microthrissa royauxi, the royal sprat, is a species of pelagic, freshwater fish from the herring family Clupeidae which is found in the Congo River basin in west Africa. It was described in 1902 by the Belgian-British zoologist George Albert Boulenger. It is of limited importance as a food fish in subsistence fisheries and its conservation status is Least Concern.
Hydrocynus forskahlii, the elongate tigerfish, is a species of predatory characin from the family Alestidae which is found in northern and western Africa.
Thalassotitan is an extinct genus of large mosasaurs that lived during the late Maastrichtian of the Cretaceous period in what is now Morocco, around 67 to 66 million years ago. The only known species is T. atrox, described in 2022 from fossils discovered in the Ouled Abdoun Basin, initially identified as coming from other genera such as Mosasaurus or Prognathodon. Hypothetical Thalassotitan specimens may have been found in other corners of the world, although researchers also note the possibility that they come from distinct, related taxa. It is considered to be close to the genera Prognathodon and Gnathomortis, together forming the tribe Prognathodontini. The prognathodontines are separated from other mosasaurs based on their massive jaws and robust teeth.
[11] [9] [6] [13] [14] [10] [15]