Eel, Conger

Conger conger

Method of production — Caught at sea
Capture method — All applicable methods
Capture area — North East Atlantic (FAO 27)
Stock area — Europe
Stock detail — All Areas
Picture of Eel, Conger

Sustainability rating five info

Sustainability overview

Updated April 2019.

Although there is no stock or fishery assessment, the species is vulnerable to the effects of fishing and catches have declined significantly in recent years. All females caught are unlikely to have bred, as females are believed to spawn once and die shortly after. Some congers are landed in the UK, and there is interest from recreational angling, but there is no management of the stock in place.

Biology

Conger eel is found in the north-east Atlantic, specifically around the shores of Iceland, west of Ireland, throughout the Celtic and North Seas, the coastal Mediterranean and the western coasts of Spain and western North Africa. The life history of the European conger eel is not well documented. It is demersal, living in rocky and sandy seafloor habitats anywhere from 10-1000m depth. It stays near coasts when young and moves to deeper waters when it matures, between 5 and 15 years old. Females undergo dramatic changes in size and skeletal structure when they reach sexual maturity, including loss of teeth, resulting them being unable to eat and subsequently dying after reproduction. There are differing opinions on whether males undergo a similarly dramatic change, and therefore whether they can reproduce multiple times in their lives. Spawning areas are thought to be in the deep sea, with known or suspected spawning grounds being in the Mediterranean, near Sardinia, and in the NE Atlantic, near the Azores. Larvae are then dispersed by currents back towards coastal areas around Europe. Because young congers tend to stay in the same areas until they reach maturity, there could be a number of discrete stocks for management purposes.

Stock information

Criterion score: 0.75 info

Stock Area

Europe

Stock information

There is no stock or fisheries assessment for conger eel. In the past few years, catches have declined to among the lowest levels on record, indicating there could be a cause for concern for either fishing pressure or the stock biomass. There is increasing evidence that stocks of European conger eel are in decline, but little data about population structures. This is a species with low resilience to fishing pressure.

Management

Criterion score: 1 info

There are no specific management or conservation measures in place for this species. Although not targeted, it is commercially fished and is often caught by methods associated with relatively high levels of discards, bycatch and damage to the benthic environment. The life history of the species means that the greatest concern is for the effect of fishing on juvenile conger eels. Because females spawn once and then die, probability suggests that at least half of catches will be from immature adults or at least those that haven’t yet spawned. As juveniles stay near the coast and only move offshore once mature, inshore fisheries are particularly likely to be targeting juveniles.

Capture Information

Criterion score: 0.5 info

Conger eels are caught mainly as bycatch in bottom trawl and demersal long line fisheries targeting groundfish and deep water species. These methods are associated with relatively high levels of discards, bycatch and damage to the benthic environment. It may also be caught by rod and line in recreational fisheries, which are more targeted and generally have lower impacts on bycatch species and habitats.

Alternatives

Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below. Click on a name to show the sustainable options available.

Basa, Tra, Catfish or Vietnamese River Cobbler
Cod, Atlantic Cod
Coley, Saithe
Haddock
Hake, European
Monkfish, Anglerfish
Pollock, Alaska, Walleye
Sturgeon (Farmed)
Tilapia

References

Casadevall, M., Sarra-Alarcon, L., Delgado, E. and Matallanas, J., 2017. The sexual segregation of the European eel, Conger conger (Linnaeus, 1758) (Anguilliformes, Congridae) and female semelparity in the north-west Mediterranean. J Fish Res. 2017; 1(1):5-14.

Correia, A. T., Alberto & Barros, Filipe & Sial, A.. (2011). Stock discrimination of European conger eel (Conger conger L.) using otolith stable isotope ratios. Fisheries Research. 108. 88-94. 10.1016/j.fishres.2010.12.002.

FAO, 2019. Species Fact Sheets: Conger conger. Available at http://www.fao.org/fishery/species/2994/en [Accessed on 01.11.2019].

Froese R. and Pauly D. (Editors), 2019. Conger conger, European conger. Available at: https://www.fishbase.in/summary/conger-conger.html [Accessed on 01.11.2019].