Conger eel

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Conger eel
Conger conger

Conger ( Conger conger )

Systematics
Subclass : Real bony fish (Teleostei)
Cohort : Elopomorpha
Order : Eel-like (Anguilliformes)
Family : Conger eels (Congridae)
Genre : Conger
Type : Conger eel
Scientific name
Conger conger
( Linnaeus , 1758)

The conger eel ( Conger conger ) or also called sea eel is a species from the genus Conger of the Congridae family . With a maximum length of up to 3 m, the conger eel is one of the largest eels in the world.

features

The long, cylindrical body of the conger eel has no scales. He has two well-trained pectorals . The beginning of the dorsalis , which extends over the entire body, lies above the posterior end of the individual pectorals . The dorsalis and analis are fused with the caudalis at the posterior end . The upper jaw of the conger eel is slightly longer than the lower jaw. Both jaws are each equipped with two rows of teeth.

Distribution and way of life

The distribution area of the species extends in the east Atlantic from Norway and Iceland to Senegal . The species is also at home in the Mediterranean and the Black Sea . In the Pacific it is found in the cold waters of the Humboldt Current off the coasts of Chile and Peru, where it is a popular food fish. The conger eel lives mainly benthal on stony and sandy soils, between stones and in holes. It can be found at depths of 0–1000 m, although the animals usually move to deeper waters when they are older. The maximum life expectancy of C. conger is estimated at approx. 20 years, with a maximum weight of approx. 110 kg.

Reproduction

Males become sexually mature at an age of approx. 5 years and a length of approx. 70 cm . Female conger eels, on the other hand, reach sexual maturity at around 15 years and around 200 cm in length. It is assumed that the C. conger population of the Mediterranean gathers for reproduction in two spawning grounds: on the one hand in the deep waters off the south coast of Sardinia and on the other hand in the south of the Adriatic Sea . During the spawning season , the adults stop feeding and morphological changes take place: the teeth begin to fall out, the digestive tract is regressed and the gonads enlarge. During egg-laying, a single female produces 3 to 8 million eggs, which are released into the water for fertilization. Due to the strong morphological changes, the adults die after the spawning season. The newly hatched larvae begin to migrate into shallower waters, in which they stay until sexual maturity.

nutrition

The conger eel is a nocturnal hunter, with its prey mainly consisting of fish , crustaceans and cephalopods . Furthermore, animals of the same species were occasionally found in stomachs, which shows that C. conger also feeds on cannibalism .

A study of the stomach contents of the conger eel populations of the Mediterranean showed that these animals do not prefer any particular prey, which is why it is assumed that they are opportunistic predators. Another study in which the stomach contents of C. conger populations in waters around Ireland were analyzed, however, showed that these populations mainly hunted 2–3 species of fish and are therefore specialized predators.

meaning

The local demand for C. conger in commercial fisheries has increased in recent years. However, this type of fish is rarely actively fished, but is mostly landed as bycatch . Due to low demand, the species is classified as "not endangered" on the Red List of Threatened Species .

The conger eel is harmless to humans. However, ciguatera fish poisoning after eating conger eel meat has been reported.

Systematics and synonyms

The conger eel was first described in 1758 by Carl von Linné under the scientific name Muraena conger in its 13th edition of the Systema Naturae . In the same year, Carl von Linné changed the name to what is now the official scientific name of Conger conger ( Linnaeus , 1758). Furthermore, C. conger is known in the literature under various synonyms :

  • Anguilla conger Linnaeus , 1758
  • Anguilla obtusa Swainson , 1839
  • Conger communis Costa , 1844
  • Conger niger Risso , 1810
  • Conger rubescens Ranzani , 1839
  • Conger verus Risso , 1827
  • Conger vulgaris Yarrell , 1832
  • Leptocephalus candidissimus Costa , 1832
  • Leptocephalus conger Linnaeus , 1758
  • Leptocephalus gussoni Cocco , 1829
  • Leptocephalus inaequalis Facciolà , 1883
  • Leptocephalus lineatus Bonnaterre , 1788
  • Leptocephalus morrisii Gmelin , 1789
  • Leptocephalus pellucidus Couch , 1832
  • Leptocephalus spallanzani Risso , 1810
  • Leptocephalus stenops Kaup , 1856
  • Leptocephalus vitreus couch , 1853
  • Muraena conger Linnaeus , 1758
  • Muraena nigra Risso , 1810
  • Ophidium pellucidum couch , 1832
  • Ophisoma obtusa Swainson , 1839

Individual evidence

  1. a b c d J. C. Quero, JC Hureau, C. Karrer, A. Post, L. Saldanha (eds.): CLOFETA: Check-list of the Fishes of the Eastern Tropical Atlantic . tape 1 . Unesco, 1990, ISBN 92-3002620-4 , pp. 156-167 ( google.de ).
  2. ^ W. Fischer, Gabriella Bianchi, William Beverley Scott: FAO Species Identification Sheets for Fishery Purposes: Eastern Central Atlantic: Fishing Areas 34, 47 (in Part) . Ed .: arrangement with the Food and Agriculture Organization of the United Nations by the Department of Fisheries and Oceans, Canada. tape 1 , 1981.
  3. a b c d Sanja Matić-Skoko, Josipa Ferri, Pero Tutman, Daria Skaramuca, Domagoj Đikić, Duje Lisičić, Zdenko Franić, Boško Skaramuca: The age, growth and feeding habits of the European conger eel, Conger conger (L.) in the Adriatic Sea. In: Marine Biology Research. Volume 8, number 10, 2012, pp. 1012-1018. (Digitized version)
  4. Sanja Matić-Skoko, Pero Tutman, Mirela Petrić, Daria Skaramuca, Domagoj Đikić, Duje Lisičić, Boško Skaramuca: Mediterranean moray eel Muraena helena (Pisces: Muraenidae): biological indices for life history. In: Aquatic biology. Volume 13, Number 3, 2011, pp. 275-284. (Digitized version)
  5. a b Alberto T Correia, Ana A Ramos, Filipe Barros, Gonçalo Silva, Paul Hamer, Pedro Morais, Regina L Cunha, Rita Castilho: Population structure and connectivity of the European conger eel (Conger conger) across the north-eastern Atlantic and western Mediterranean: integrating molecular and otolith elemental approaches. In: Marine biology. Volume 159, Number 7, 2012, pp. 1509-1525. (Digitized version)
  6. M. Casadevall, L. Sarrà-Alarcón, E. Delgado, J. Matallanas: The sexual segregation of the European eel, Conger conger (Linnaeus, 1758) (Anguilliformes, Congridae) and female semelparity in the northwest Mediterranean. In: Journal of Fisheries Research. Volume 1, Number 1, 2017, pp. 5-14. (on-line)
  7. ^ S. O'Sullivan, C. Moriarty, J. Davenport: Analysis of the stomach contents of the European conger eel Conger conger in Irish waters. In: Journal of the Marine Biological Association of the United Kingdom. Volume 84, Number 4, 2004, pp. 823-826. doi: 10.1017 / S0025315404010008h
  8. G. Relini, C. Piccinetti: Ten years of trawl surveys in Italian seas (1985-1995) . Ed .: FAO, Rapport sur les Peches. 1996, ISSN  1014-6555 .
  9. ^ Arthur E Dammann: Study of the fisheries potential of the Virgin Islands . Ed .: Virgin Islands Ecological Research Station. No. 1 , 1969, p. 197 . (Digitized version)
  10. ^ WoRMS Editorial Board: World Register of Marine Species (WoRMS). In: WoRMS. WoRMS Editorial Board, 2018, accessed October 16, 2018 .

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