Which Species of Fish Should be Returned?

Throughout the twentieth century the human demand for all manner of seafood combined with commercial overfishing and insane EU discard policies have seen the stocks of many fish species hit record lows. Long-living, late maturing species such as sharks are particularly vulnerable, and intensive trawling makes species which live and feed on the seabed such as skates, rays and wolffish have also been seriously reduced in number.

Thankfully there have been some moves to make commercial fishing more sustainable, such as using nets which are less damaging to the seabed, and new legislation such as the discards ban (which is hopefully forthcoming) will help stocks recover as well. Despite this good news there are still a number of species in the seas around the British Isles which are in real trouble. Indeed, some species such as the silver eel, shad and now bass are so depleted in number that they have UK-wide (or in the terms of bass EU-wide) legal protection, making it an offence for anyone to retain these species if they catch them. However, many other species which are critically endangered have no legal protection at all.


Commercial fishing vessels – especially large vessels such as the 2500 ton Polish trawler Polnus – are a key factor for the reduced fish stocks of today.

Fishing from the shore with a rod and line is one of the least damaging ways of taking fish from the sea. Compared to commercial vessels anglers take a tiny amount of fish from the sea while adding a great deal of money to local economies through buying equipment, bait and other goods and services.

Catch and Release Carp Competition

Many anglers, such as the ones above pictured at a carp competition in America, practice catch and release fishing.

One of the best aspects of angling is that, unlike commercial trawlers which indiscriminately scoop everything out of the sea, anglers can be selective about the fish they keep and return any fish which are endangered, threatened or simply unwanted. Read on to find out which species can be helped by anglers returning them to the sea if they are lucky enough to catch them.

Shark Species (Bull Huss, Smooth-hound, Spurdog, Tope)

Smooth-houndMany people are surprised to hear that there are a number of shark species found around Britain. However, many of these species are classed as Threatened by the IUCN (International Union for the Conservation of Nature): tope, smooth-hound and spurdog are all classed as Vulnerable and bull huss are classed as Near Threatened. As well as this almost all of the major shark species which are found in UK waters such as porbeagle, blue, mako, and basking sharks are all also on the threatened list, and angel shark (featured below) are critically endangered. The only shark species which is not threatened in the seas around the UK is the small and humble lesser-spotted dogfish.

It is the usual culprit of commercial fishing which has depleted shark numbers around most of the world, with stocks of spurdog reduced to 5% of their pre-commercial abundance in certain international waters where fishing is unregulated. All shark species are commercially valuable with the flesh eaten, skin used for leather and the liver utilised for oil. Furthermore, there is massive demand for shark fins in China and other parts of Asia and many of the small shark species around the UK are now being caught and exported to these countries for this purpose. A further problem is that shark species may also be caught as bycatch by commercial vessels targeting other species. Due to the difficulties in gutting and processing sharks, bycatch caught specimens are often thrown back into the sea dead as bycatch. All sharks species are slow growing and late maturing, which means that in areas where they have been reduced in number it will be take a very long time for stocks to recover, even if commercial fishing stops entirely, and in areas which are still subject to intensive commercial pressure the outlook for these shark species is bleak.

Why they are a species that you should consider returning: Little can beat the prestige of catching a decent sized shark species from the shore. Since shark meat is not commonly eaten in the UK it makes sense for anglers to return any of the shark species that have been caught (after a few photos have been taken) to increase the chance of the species breeding and hopefully increasing stocks for future generations to continue catching shark species around Britain.

Atlantic Wolffish

WolffishAtlantic wolffish have been massively reduced in number on both sides of the Atlantic. This is mostly down to commercial fishing. Wolffish are a bottom dwelling species which spends most of its time hidden away in rocks and crevices and emerging only to feed on crabs, lobsters and shellfish. They also reproduce in an unusual way as the female lays eggs which stick to stones and seeweed forming a nest which the male protects until the eggs hatch, which can take four or five months. Atlantic wolffish also mature late, with some claims that they have to be ten years old before they can reproduce.

Atlantic wolffish are commercial valuable. Although the vast majority of the general public would not be able to identify this species they are commonly sold in fish and chip shops, especially in the north of England where they are known as Woof, or Scarborough Woof. The liver is also valuable for its oil. Modern commercial fishing methods have decimated the numbers of Atlantic Wolffish as being a fish which lives and feeds exclusively on the seabed they have no way of escaping the nets of trawlers. Furthermore, the nests of eggs are also destroyed and dispersed by trawler’s nets, making the replenishment of Atlantic wolffish stocks extremely difficult to achieve. However, anglers also have to take some of the blame for the plight of the wolffish as boat anglers taking large specimens throughout the 1960s and 70s removed much of the prime breeding stock of this species, exacerbating the problems which are being faced now.

Why they are a species that you should consider returning: Atlantic wolffish are a rare and unusual fish which is seldom caught by shore based anglers in the United Kingdom. Due to the seriously depleted numbers of this species the best course of action would be to return any specimens which are caught in order to give them a chance to reproduce.

Angel Shark

Angel SharkAngel shark are a strange looking animal. Although they look a lot like a ray or very large flatfish they are in fact a true shark species. Angel shark are adapted to living and feeding on the seabed where they hunt for all manner of bottom dwelling fish. Like most shark species they are slow growing and late maturing and produce a relatively low number of young. They have little commercial value with only a limited value for human consumption of the flesh in some European countries, although numbers of these species are so low now any market for this species is no longer viable.

Angel sharks were once abundant in European waters but have been practically wiped out by modern commercial fishing methods – as trawlers drag heavy, weighted nets over the seabed they easily catch the bottom dwelling angel shark. Numbers of this species have dropped to such an extent that the ICUN places them in the most serious category of Critically Endangered, meaning that they face an extremely high risk of being declared extinct in the near future. To put this into perspective the angel shark is considered at a higher risk of becoming extinct than the giant panda, snow leopard or Asian elephant. The species is thought to be extinct in the North Sea and in Irish waters where it was once common, with the only limited groups surviving off the north African coast, sporadic dispersed populations within the Mediterranean, and these is a protected area which holds angel shark around the Canary Islands.

Why they are a species that you should consider returning: Angel sharks are truly teetering on the very edge of extinction. Due to their massively reduced numbers it is near-impossible for a UK shore angler to catch this species. However, if one was caught against the odds then the only thing to would be to return it to the sea as there is no justification at all for killing and keeping a species as seriously in trouble as the angel shark.

Conger Eel

Conger EelConger eels are fairly common around the UK, especially around the western coastline. They are fast growing and are not thought to be endangered with numbers being fairly healthy in some parts of the UK. Conger eels live in European waters until they are between five and ten years old. They then undergo an unusual change where they stop feeding and their skeleton weakens and changes shape. Following this they migrate to the tropical areas of the Atlantic Ocean where they spawn and then die. The eggs then hatch and the young eels head for Europe to start the process all over again.

Why they are a species that you should consider returning: UK anglers work on a minimum size system which is designed to allow fish to breed at least once before they can be caught and kept by anglers. However, the conger eels reproductive pattern means that the minimum size system is irrelevant – if a conger eel is present and feeding in British waters it cannot possibly have reproduced as they only do this in the tropics. Large conger eels may be on the very verge of undergoing the journey to migrate and spawn and so are the very worst specimens to kill and keep. Conger eels are one of the best sporting species that UK anglers can catch, and offer anglers a realistic chance of catching a good-sized specimen from the shore. Every conger eel which is killed by anglers reduces the number of young which will return from the tropics to re-populate British waters, and anglers should consider returning every conger eel they catch to maintain the healthy numbers of this species. No one wants to see a large British species such as conger eel go the same way as the common skate (see below).


MulletWhile mullet (the thin lipped grey, thick lipped grey and golden grey, not the red mullet which is not a true mullet species) are fairly common around the UK. Although they are eaten in Europe they have little demand as a food fish in Britain, and commercial vessels largely ignore this species.

Why they are a species that you should consider returning: Despite the fact that mullet are common and rarely commercially targeted it is still a good idea for anglers to return them to the sea. This is because mullet are a very slow growing and late maturing species, meaning that if numbers are reduced it will be very difficult to replenish stocks. Many mullet which have reached the UK minimum size of 13 inches (33cm) are still too small to have reproduced, indeed, the Angling Trust believes that mullet have to be around 18½ inches (47cm) in length and between nine and twelve years old before they can reproduce. The mullet is a unique seafish which provides a great challenge for anglers around the UK. It is best to return this fish to the sea whenever possible to safeguard numbers.

Skate and Ray Species

Eagle RayAs species which are adapted to live and feed on the seabed skates and rays are always going to be at a high risk of being caught in the nets of commercial trawlers, and this has certainly played a big role in reducing numbers of these species. Skate and ray have some commercial value and are caught as bycatch and retained for their edible flesh, although the unusual shape and difficulty in processing and filleting mean that often they are simply thrown back into the sea dead. However, anglers must also take some of the blame for the reduction in number of these species – particularly skate. Due to their large size (200lb+) skate were a highly prized catch for boat anglers, who would constantly target large, mature skate. Anglers would often kill any skate they caught in order to take them back to shore to photograph. After the photographs had been taken anglers would simply throw the skate back into the sea off the end of a pier or from a harbour wall. Such behaviour had a devastating impact on skate numbers, especially as skate are non-migratory meaning that whole areas have been pretty much entirely fished out of this entire species which was once common around much of the British Isles. Today the skate is classed as Critically Endangered by the IUCN (International Union for the Conservation of Nature) meaning that it is at an extremely high risk of being declared extinct in the very near future. The many species of ray which are found in UK waters the vast majority are on the IUCN Theatened Species Scale:

  • Blonde ray – Near Threatened
  • Bottle nosed ray – Endangered
  • Sandy ray – Vulnerable
  • Small eyed ray – Near Threatened
  • Starry ray – Vulnerable
  • Thornback ray – Near Threatened
  • Undulate ray – Endangered

Common stingray and the electric ray are classed as Data Deficient which means that the IUCN has not been able to gather enough information to come to a conclusion about the state of the numbers of these species. The cuckoo ray and the spotted ray are the only ray species which are classed as being of Least Concern by the IUCN. To make things worse skate and ray species, are, like the shark species they are closely related to, very slow growing and late maturing, meaning that they need to be around five to seven years old before they can reproduce. This late maturity means that number will take a long time to recover even if commercial fishing intensity reduces.

Why they are a species that you should consider returning: All rays should be returned for the simple reason that they are massively depleted in number and need all the help they can get to restore stocks. Skate are a very rare catch from the shore these day but should also be returned due to their critically endangered status.

Shad and Silver Eels

ShadShad and silver eels are all similar in the fact that they are both anadromous species, meaning they can live and migrate between both freshwater rivers and the sea. Silver eel are born in the tropical Sargasso Sea and take the form of elvers. They then make the journey of thousands of miles to Europe where they transform into glass eels and swim up rivers and live in freshwater. Once here they change yet again and become yellow eels. Once they are aged anywhere between ten and thirty-five years they will transform for a final time into silver eels migrate to the sea and live there for several years before making the journey to the Sargasso Sea where they spawn and then die. Once the eggs hatch the young will begin to swim to Europe to begin the process again. Shad effectively migrate in the reverse way to silver eels. The mature shad live in the sea and then swim a long distance – up to several hundred miles – inland to spawn and lay their eggs in freshwater rivers. The young fish live in freshwater before returning to the sea once they are fully grown and live there until breeding season when they will return to the freshwater rivers again.

One of the main reasons that these species are plummeting in number is that the rising number of dams, pumping stations and other obstructions are stopping them from following their natural migration patterns which is seriously depleting numbers. However, eels are also intensively commercially exploited at every stage of their life:

Why they are a species that you should consider returning: Shad are a protected species and any angler catching an allis or twaite shad must return the fish to the water unharmed and as quickly as possible. There was a ban on anglers retaining silver eels in 2009 and 2010, and while this has lapsed there are many regional and local bans and bye-laws on taking silver eels, and in many parts of the UK taking silver eels from the sea remains and offence. However, all responsible anglers would return silver eels to the sea regardless of whether or not they are legally compelled to as this species is seriously depleted and everything possible needs to be done to try and increase numbers.

Some anglers will argue that they have the right to keep any fish they catch which is not a protected species and is above the minimum size limit. This is true but is an extremely short-sighted way of viewing the sport of sea fishing. The species featured above are all brilliant sport species which all anglers love catching. It makes sense to protect these species by returning them to the sea and only retaining species which are more robust in numbers and stocks.

Sea Trout and Salmon

SalmonDespite the name there is no such thing as a trout which spends its entire life in the sea – all trout are anadromous meaning they will migrate between salt and fresh water in their lives, the same is true of salmon. A licence is needed to keep trout and salmon, even if they have been caught in salt water. Although they are a fairly rare catch an angler plugging for bass or spinning for mackerel or pollock who catches a trout or salmon must return it to the sea if they do not have a licence.

Why they are a species that you should consider returning: They can be kept by anglers with a licence, but it is illegal for non-license holding anglers to retain these species – any angler taking these species without a licence and being caught faces prosecution.


Bass are a species which has had its numbers seriously depleted in recent years, leading to a range of measures being put forward by the European Union to try and halt the decline in bass numbers in Europe’s waters. For this reason bass were a catch-and-release only species for anglers in the first half of 2016, and only one bass per angler could be retained in the second half of this year. The minimum retention size of this species was also increased to 42cm. The same restrictions were in place for anglers for 2017, and in 2018 bass will be a catch-and-release only species for the entire year.

Why they are a species that you should consider returning: Returning this species is a legal requirement in 2018. For much more information on this issue please read our article Europe’s Bass – A Species on the Edge of Collapse?

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