- Scientific name: Conger conger
- Also known as: European Conger
- Size: Maximum size unknown, at least 200lbs (UK shore caught typically 5-25lbs)
- UK minimum size: 36inches (91cm) in length (but see below)
- UK shore caught record: 68lb 8oz
- IUCN Status: NE (Not Evaluated)
- Distribution: Conger eels are mostly found around the western coast of the British Isles but can be elsewhere in Britain, including along the eastern coast, but in much smaller numbers. Their range extends throughout European waters.
- Feeds on: Predator which will hunt down and fish species it can find, but will also happily feed by scavenging for dead or rotting fish.
- Description: Long snake-like muscular body. Scaleless skin which is dark grey, bluish or green in colour. Dorsal fin ranges all the way around the body and merges with anal fin. Upper jaw extends beyond lower jaw. Relatively large eyes and prominent lips with mouth full of small, sharp teeth.
Due to their size and the fact they always put up a strong fight when caught with rod and line conger eels are a highly-rated catch amongst sea anglers. Always popular as a target for boat anglers, especially those fishing over wrecks, it is perfectly possible to catch big conger from rock marks and very rough ground on the shore, mostly around the west and south of the UK. Conger eels of up to 25lb are potential catches from the shore, with a few eels over the 40lb mark lurking around as well. Interestingly, larger conger eels are always female, with males reaching a maximum of around 35lb, and usually averaging half of this. The very biggest conger eel live out at sea in deep water, where they often live in wrecks and are targeted by boat anglers. The size conger eel can actually reach is unknown. Eels in excess of 200lb have been caught in commercial trawler’s nets, and a specimen weighing 350lb was reportedly caught by a trawler near the island of Vestmannaeyjar off the south coast of Iceland. Very large conger eels are certainly present in British waters. In May 2015 a 7ft long conger eel was caught in the nets of a trawler off the coast of Devon and weighed 133lb after being gutted. The current UK shore record is an eel of 68lb 8oz, caught at Devil’s Point, Plymouth in 1992, while the British boat record is 133lb 4oz, and was set in 1995.
Due to spawning in the Atlantic Ocean conger eels are much more common along the western and southern coast of the British Isles, although the can be caught along the eastern coastline of England and Scotland but they are present in much smaller numbers in these locations. The range of conger eels extends into Scandinavian waters and southwards into African waters as far the coast of Senegal. They are also found throughout the Mediterranean Sea and in parts of the Black Sea.
Feeding and Behaviour
Conger eels inhabit rocky ground and spend most of daylight ours hidden away in caves or other small spaces, and come out to feed at night, although in deep water which sunlight does not reach they will feed at any time. Conger eels will either wait and ambush fish or swim around freely to hunt, although they are also happy to scavenge along the sea bed for dead, rotting or injured fish. Very occasionally conger eels will emerge from their rocky homes under the cover of darkness and hunt over mixed ground, or even sandy seabeds, meaning they can turn up unexpectedly in anglers’ catches. Despite their fearsome reputation divers observing congers in the wild have found them to be fairly passive creatures which simply ignore any fish which are too big to eat, and even retreat into their lairs when threatened. However, in 2013 a diver in Killary Fjord, County Galway in the Republic of Ireland was reportedly attacked by a conger eel while at a depth of twenty-five metres. The eel bit into the man’s face and thrashed around, removing a chunk of flesh from the man’s cheek. More information and a fairly graphic image of the injuries the conger eel inflicted on the man is available by clicking here. Attacks such as this are incredibly rare and conger eels are believed to pose a minimal threat to humans. Indeed, this attack may have been explained by the conger eel mistaking a part of the man’s wet suit or a flash of light from his face mask for a small fish, leading to the attack.
When hooked by an angler conger eels are famed for putting up a strong fight and often spin and thrash when taken from the water. Care must always be taken when landing and unhooking a big conger eel.
Differences Between Conger and Silver Eel
Conger eel are occasionally confused with the silver eel but the differences between the two species are fairly clear. The dorsal fin of the conger eels starts level with the pectoral fins, while the dorsal fin of the silver eel starts far back along the body. Another telltale sign is the jaw: with conger eel the upper jaw protrudes furthest, whereas in silver eel the lower jaw juts out noticeably. See our guide to the difference between these species by clicking here.
Reproduction and Breeding
Conger eel are extremely fast growing, with a report in The Fisherman’s Handbook from 1977 stating that a 3lb conger kept in Southport Aquarium reaching 69lb in four years, and another of a similar starting size reaching 90lb in five years. Despite this fast growth rate little is known about the ages at which conger become sexually mature. It is thought that males may need to reach at least five years old to reproduce, and females need to be up to ten. Once they are able to reproduce the conger has a very interesting and unusual breeding cycle. At some point after the conger has become sexually mature major changes take place in the conger: they stop feeding altogether, the skeleton loses mass and becomes much weaker and the head changes shape, the males eyes enlarge, the females body swells up massively. The conger then swims several thousand miles to the tropical and sub-tropical areas of the Atlantic, Azores and Sargasso Sea. Once there the female conger will lay eggs which are fertilised by the male. Shortly after this is done both conger eels will die. The fertilised eggs float in the sea before the eels hatch. After two years the young eels will be around six inches in length and will begin the long journey back to Europe where they live before reaching sexual maturity and undertaking the whole process all over again. Because of this breeding cycle it means that any conger caught from the shore – indeed, any conger which are feeding – cannot have reproduced. For this reason it is best to return any caught conger eel to the sea to allow them to live and hopefully one day swim to the tropics to reproduce and therefore maintain populations. Conger are extremely tough and hardy and can survive being out of the water for a long time and so make ideal candidates for catch-and-release fishing. As well as this flesh of the conger eel has little appeal in terms of eating. Conger are not exactly a common shore catch so anglers should do all they can to ensure that conger populations are maintained and this species is around for future generations of anglers to enjoy catching (and releasing).
Conger eels are not targeted by commercial fishing vessels, although they are sometimes caught as bycatch when targeting other species. Due to the poor reputation of conger eels as a food fish there is only a very limited market for this species, and conger eels are often discarded at sea by commercial vessels, although in some European countries they are retained to turn into fishmeal or even use as bait in crab and lobster pots..
Methods and Techniques to Catch Conger Eel
Smaller congers – usually referred to as strap conger – often take baits meant for other species such as ray and cod. However, due to the potential size of conger eels, and the rough ground they inhabit, anglers specifically targeting big conger eels require heavy-duty tackle. Stiff beachcasters, big multiplier reels are the right equipment to hook and land a big eel. Generally it is heavy rock marks which give access to deep water which hold conger, meaning long casting distances are rarely needed when fishing for conger eels. Rigs with wire snoods or very heavy 150lb+ mono are usually used as the conger’s sharp teeth can cut through normal mono, and heavy gauge hooks sized 6/0 – 10/0 are the right size.
By a long way mackerel baits are the most commonly used to catch conger with mackerel flappers, mackerel heads, mackerel fillets and full small mackerel all proven to catch conger. However, full large squid, cuttlefish and bluey can also catch big eels, while some anglers have success using rocking or pouting as bait, as these species are likely food sources which conger eels will come across in their natural environment. The very roughest and heaviest ground has the highest chance of being home to a conger eel, and tackle loss will inevitably be high. For this reason anglers should incorporate some sort or rotten bottom or weak link release into the rigs they use – have a look at the short range conger rig featured in the Rigs Section of this website. Knowing when to strike a conger bite can be difficult as conger can be surprisingly shy biters, so it is wise to give them time to take a bait fully before striking and reeling in. However, if a conger is given too long it may well make its way into a hole or manage to wedge itself into a crevice or crack. If this happens a decent-sized conger will likely be impossible to budge and the angler will have no choice other than to pull until the line breaks. Knowing when to strike and reel in with conger eels is a matter of judgement (and to a certain extent luck). It is also wise to leave the reel on the ratchet so that a conger taking and moving off with a bait will take line and give an audible warning. Using this method eliminates the risk of the rod being pulled into the sea – something a large conger eel is more than capable of doing.