| Giant mottled eel | |
|---|---|
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Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Anguilliformes |
| Family: | Anguillidae |
| Genus: | Anguilla |
| Species: | A. marmorata |
| Binomial name | |
| Anguilla marmorata | |
| Synonyms | |
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The giant mottled eel (Anguilla marmorata), also known as the marbled eel, is a species of tropical anguillid eel that is found in the Indo-Pacific and adjacent freshwater habitats. [2]
Similar to other anguillids, the giant mottled eel is cylindrical with small, well-developed pectoral fins and a protruding lower jaw. [3] The eel has thick, fleshy lips. [3] The eel has dorsal and anal fins that are continuous around the tail, with the origin of the dorsal-fin between the pectoral fins and anus. [3] It has small, oval-shaped scales that are embedded in the skin. [3]
Unlike some other anguillid species, this species has a mottled color. [2] [3] The adult eels are yellow with a greenish-brown to black marbling on their back and a white belly. [2] [3] The young elvers have less visible marbling and are grayish to yellow. [2] [3] The dorsal fin of the marbled eel is closer to the gill opening than to the anus, more anterior than other species of Anguilla . [3] Like all anguillid eels, it does not have pelvic fins. [4] The head is rounded and the snout is depressed. [4] Its teeth are small and in bands. [4] It has a total of 100 to 110 vertebrae. [2]
It can grow up to 2 meters (6.6 ft) for females and 1.5 meters (4.9 ft) for males and can weigh up to 20.5 kilograms (45 lb), [2] making it the largest species of anguillid eels. The marbled eel can live up to about 40 years. [3]
This anguillid species can be found from East Africa to French Polynesia and as far north as southern Japan. [2] [3] [5] In Africa, it may be found within Mozambique and the lower Zambezi River. [2] The giant mottled eel has the widest distribution of all the Anguilla eels. [3] [6] It is usually found in tropical climates between 24°N to 33°S. [2] It has also been found in other more distant regions such as the Galapagos possibly due to abnormal larval transport associated with El Niño-Southern Oscillation events. [7] It is not on the IUCN Red List of Threatened Species, but in Taiwan, it is endangered. [3] [8]
In 2002, a single eel was captured from a pond close to Kaupo, Maui, Hawaii, though it is not indigenous to the area. [3]
The adults of this species are demersal, living on the bottom of fresh to brackish waters, in rivers, lakes, and tributaries. [2] This species and all anguillid eels are catadromous, migrating sometimes long distances out into the open ocean to spawning over deep water. [2] A spawning area of this species is known to be west of the Mariana Islands in an area of the North Equatorial Current in the western North Pacific, but other spawning areas are thought to exist in the western South Pacific and Indian Ocean. [9]
Marbled eels spend their adult lives in freshwater or estuarine habitats, and migrate to the ocean to reproduce. [3] When the eggs hatch, the leptocephali drift in ocean currents for months until they reach estuaries as glass eels where they migrate upstream into freshwater as elvers. [3] Then, after about 8 to 20 years in brackish or freshwater, the yellow eels grow up into silver eels (mature eels), and they return to the ocean for reproduction. [3]
The marbled eel is carnivorous, but harmless, with a wide-ranging diet, eating shrimp, crabs, bony fish, and frogs. [10] It is nocturnal, so it is active at night. [10]
Like other anguillid eels, this species is used as a source of food in some regions. [3] Some restaurants buy live eels. [3] In 1992, for example, a typical 12 kilogram (26.5 lb) marbled eel retailed for one thousand US dollars in China. [3] [11]
An eel habitat, Cheonjiyeon Waterfalls' pond, is a natural monument in South Korea. [12]
Large individuals of this species are also highly regarded and are not harmed by native people in some island groups of the western Pacific.
Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres. Such migrations are usually done for better feeding or to reproduce, but in other cases the reasons are unclear.
The European eel is a species of eel. They are critically endangered due to overfishing by fisheries on coasts for human consumption and parasites.
The American eel is a facultative catadromous fish found on the eastern coast of North America. Freshwater eels are fish belonging to the elopomorph superorder, a group of phylogenetically ancient teleosts. The American eel has a slender, supple, snake-like body that is covered with a mucus layer, which makes the eel appear to be naked and slimy despite the presence of minute scales. A long dorsal fin runs from the middle of the back and is continuous with a similar ventral fin. Pelvic fins are absent, and relatively small pectoral fins can be found near the midline, followed by the head and gill covers. Variations exist in coloration, from olive green, brown shading to greenish-yellow and light gray or white on the belly. Eels from clear water are often lighter than those from dark, tannic acid streams.
Eels are any of several long, thin, bony fishes of the order Anguilliformes. They have a catadromous life cycle, that is: at different stages of development migrating between inland waterways and the deep ocean. Because fishermen never caught anything they recognized as young eels, the life cycle of the eel was a mystery for a very long period of scientific history that continues into the present day. Of significant interest is the search for the spawning grounds for the various species of eels and identifying impacts to population decline in each stage of the life cycle.
The short-finned eel, also known as the shortfin eel, is one of the 15 species of eel in the family Anguillidae. It is native to the lakes, dams and coastal rivers of south-eastern Australia, New Zealand, and much of the South Pacific, including New Caledonia, Norfolk Island, Lord Howe Island, Tahiti, and Fiji.
Moray eels, or Muraenidae, are a family of eels whose members are found worldwide. There are approximately 200 species in 15 genera which are almost exclusively marine, but several species are regularly seen in brackish water, and a few are found in fresh water.
The Anguillidae are a family of ray-finned fish that contains the freshwater eels. Eighteen of the 19 extant species and six subspecies in this family are in the genus Anguilla, and all are elongated fish of snake-like bodies, with long dorsal, caudal and anal fins forming a continuous fringe. They are catadromous, spending their adult lives in freshwater, but migrating to the ocean to spawn.
The Arctic lamprey, also known as the Japanese river lamprey or Japanese lampern, is a species of lamprey, a jawless fish in the order Petromyzontiformes. It inhabits coastal freshwater habitat types in the Arctic. Some populations are anadromous, spending part of their lives in the ocean. It is the most common and widespread lamprey in the Arctic region.
The New Zealand longfin eel, also known as ōrea, is a species of freshwater eel that is endemic to New Zealand. It is the largest freshwater eel in New Zealand and the only endemic species – the other eels found in New Zealand are the native shortfin eel, also found in Australia, and the naturally introduced Australian longfin eel. Longfin eels are long-lived, migrating to the Pacific Ocean near Tonga to breed at the end of their lives. They are good climbers as juveniles and so are found in streams and lakes a long way inland. An important traditional food source for Māori, who name them ōrea, longfin eel numbers are declining and they are classified as endangered, but over one hundred tonnes are still commercially fished each year.
The speckled longfin eel, Australian long-finned eel or marbled eel is one of 15 species of eel in the family Anguillidae. It has a long snake-like cylindrical body with its dorsal, tail and anal fins joined to form one long fin. It usually has a brownish green or olive green back and sides with small darker spots or blotches all over its body. Its underside is paler. It has a small gill opening on each side of its wide head, with thick lips. It is Australia's largest freshwater eel, and the female usually grows much larger than the male. It is also known as the spotted eel.
The Pacific ladyfish, also known as the Pacific tenpounder and machete, is a species of ray-finned fish in the genus Elops, the only genus in the monotypic family Elopidae. The Pacific ladyfish can be found throughout the southwest U.S. and other areas in the Pacific Ocean.
The Indo-Pacific tarpon, also known as the oxeye herring or simply herring due to its superficial resemblance to the true herrings, of which it is not a member, is the smaller of the two species of tarpon and lives in Indo-Pacific waters.
Anguilla bengalensis bengalensis, the Indian mottled eel, is a subspecies of eel in the genus Anguilla of the family Anguillidae. It is found throughout the Indian subcontinent and neighbouring regions including the East Indies.
The mottled eel, also known as the African mottled eel, the Indian longfin eel, the Indian mottled eel, the long-finned eel or the river eel, is a demersal, catadromous eel in the family Anguillidae. It was described by John McClelland in 1844. It is a tropical, freshwater eel which is known from East Africa, Bangladesh, Andaman Islands, Mozambique, Malawi, Sri Lanka, Sumatra, and Indonesia and recently from Madagascar. The eels spend most of their lives in freshwater at a depth range of 3–10 metres, but migrate to the Indian Ocean to breed. Males can reach a maximum total length of 121 centimetres and a maximum weight of 7,000 grams. The eels feed primarily off of benthic crustaceans, mollusks, finfish and worms.
The Japanese eel is a species of anguillid eel found in Japan, Korea, Taiwan, China, and Vietnam, as well as the northern Philippines. There are three main species under the Anguilla genus, and all three share very similar characteristics. These species are so similar that it is believed that they spawned from the same species and then experienced a separation due to different environments in the ocean. Like all the eels of the genus Anguilla and the family Anguillidae, it is catadromous, meaning it spawns in the sea but lives parts of its life in freshwater. Raised in aquaculture ponds in most countries, the Japanese eel makes up 95% of the commercially sold eel in Japan, the other 5% is shipped over by air to the country from Europe. This food in Japan is called unagi; they are an essential part of the food culture, with many restaurants serving grilled eel called kabayaki. However, presumably due to a combination of overfishing and habitat loss or changing water conditions in the ocean interfering with spawning and the transport of their leptocephali this species is endangered.
The yellow-edged moray, also known as yellow-margin(ed) moray, leopard moray, and speckled moray, is a moray eel of the family Muraenidae, found in the Indo-Pacific Oceans at depths to 150 m (500 ft).
The zig-zag eel, also known as the tire-track eel, tire-track spiny eel or marbled spiny eel, is a species of ray-finned, spiny eels belonging to the genus Mastacembelus of the family Mastacembelidae, and is native to the riverine fauna of India, Bangladesh, Pakistan, Sri Lanka, Thailand, Vietnam, Indonesia and other parts of Southeast Asia. The species was described as Macrognathus armatus by Lacepède in 1800. Other common names for this popular aquarium species are leopard spiny eel and white-spotted spiny eel. This species is not only a popular aquarium fish but also as a food fish in its country of origin.
Eels are ray-finned fish belonging to the order Anguilliformes, which consists of eight suborders, 20 families, 164 genera, and about 1000 species. Eels undergo considerable development from the early larval stage to the eventual adult stage and are usually predators.
The Philippine mottled eel is an eel in the family Anguillidae. It was described by Shun Watanabe, Jun Aoyama, and Katsumi Tsukamoto in 2009. It is a tropical eel known from the Pinacanauan River system on Luzon Island, in the Philippines. The eels spend most of their lives in freshwater but migrate to the ocean to breed.
Fish go through various life stages between fertilization and adulthood. The life of a fish start as spawned eggs which hatch into immotile larvae. These larval hatchlings are not yet capable of feeding themselves and carry a yolk sac which provides stored nutrition. Before the yolk sac completely disappears, the young fish must mature enough to be able to forage independently. When they have developed to the point where they are capable of feeding by themselves, the fish are called fry. When, in addition, they have developed scales and working fins, the transition to a juvenile fish is complete and it is called a fingerling, so called as they are typically about the size of human fingers. The juvenile stage lasts until the fish is fully grown, sexually mature and interacting with other adult fish.
