Unhooking and Releasing Fish

With concerns over fish stocks, growing numbers of endangered species and increasing awareness of environmental issues, catch-and-release is becoming more and more common in sea fishing. This makes knowing how to safely and quickly unhook and release a fish back into the sea is becoming increasingly important. There are a number of reasons why anglers have to release fish such as observing minimum size limits which are imposed to protect stocks and because certain species of fish, such as silver eels and shad, are protected by law and legally must be returned if they are caught. Bass are a top target for UK anglers, but their declining numbers (read more here) have seen Europe-wide laws and regulations put in place to protect stocks. Since 2016 anglers have been legally required to fish for this species on a catch-and-release only basis for certain months of the year.

Of course, many anglers release fish not because they are legally obliged to but simply because they want to. This may be because anglers are fishing purely for sport, because they want conserve fish stocks or because they have already caught enough fish for the table and have no need to keep any additional fish. For all of these reasons, it is important that anglers are able to unhook fish quickly and return them to the sea in a way that gives them the best chance of survival.

Related article: Responsible Sea Angling

Measures to Limit Damage to Hooked Fish

Mackerel Treble Hook
Treble hooks cause great damage to fish, and should not be used if fishing on a catch-and-release basis.

Any fish which has been caught on any kind of hook will have received a certain amount of damage during the process of being caught. However, there are a number of simple measures which anglers can take to minimise the harm which is caused to fish, and give any fish which are caught and returned to the sea the very best chance of survival. Indeed, peer-reviewed scientific research shows that fish which are caught by anglers have a very high chance of surviving capture and continuing to live with minimal after-effects if they are unhooked in the proper manner and returned to their natural environment quickly.

  • Anglers should always try to ensure fish are lip-hooked and not gut-hooked (this is when the fish fully swallows the hook). Using the correct sized hooks is one way of increasing the chances of lip-hooking fish. While certain types of fishing (i.e. LRF, mini species fishing and when targeting small-mouthed species such as Dover sole) may require the use of smaller hooks, most general sea fishing will use hooks sized 1, 1/0 or 2/0 and using hooks of this size will stop the majority of fish taking the hook all the way down inside their body.
  • If small fish are constantly being gut-hooked anglers should consider switching to larger hooks to prevent this from happening.
  • Learning when to strike when a bite registers also helps lip-hook a fish as a well-timed strike drives the hook into the mouth of a fish before the fish has taken the bait and hooks all of the way down into its body.
  • Certain patterns of hooks can also help to lip-hook fish. Circle hooks are specifically designed to slide to the edge of a fish’s mouth and lip-hook the fish. These hooks also allow the fish to self-hook themselves and there is no need for anglers to strike when using circle hooks. View Koike Circle Hooks which are available in sizes 1 – 5/0 by clicking here.
  • Similarly, long-shanked hooks are ideal for anglers targeting fish that have small mouths, such as flatfish species, as they allow the hook to be removed much easier than a short shanked pattern. These types of long-shanked hooks are often referred to as flatfish hooks, such as these which are manufactured by Cronus.
  • Anglers fishing on a catch-and-release basis should also consider crushing the barbs of hooks with pliers as this will make the hooks much easier to remove from any fish. Be aware that treble hooks can cause a great amount of damage to fish and many anglers who are lure fishing remove the barbs from these hooks, or swap the treble hooks for standard J-shaped hooks. Similarly, while many plugs come with two or three treble hooks many anglers reduce this to a single treble hook to prevent causing damage to fish which are caught.


Koike Disgorger which is available from Sea Angling Shop by clicking here.

There are a number of disgorgers on the market that allow fish to be unhooked easily. Even fish that have been relatively deeply hooked can be released quickly with a disgorger (watch a video on how to do this on YouTube by following this external link). Sea fishing disgorgers can be purchased from Sea Angling Shop for only £2.89 by clicking here. When it comes to removing the hooks from the mouths of bigger fish there are specialist fishing forceps, although standard needle or long-nosed pliers bought from a DIY store can often do just as good a job. Unhooking bigger fish such as conger eel, tope and smooth-hound can be difficult to unhook and care must always be taken to avoid injury. Unhooking the largest species is usually a job for two people – one with protective gloves on to keep the fish’s mouth open while the other removes the hook.

Returning Fish with Hooks Still in their Mouths

Circle hooks (left) reduce the chances of fish being deeply hooked, and long-shanked hooks (right) are easier to remove.

If fish are too deeply hooked to unhook then there is usually no alternative other than to cut the hooks away. Simply cut the line as close to the eye of the hook as possible and release the fish in the usual manner . There is much debate about whether or not deeply hooked fish with hooks left in their mouth survive. Stainless steel hooks will not rust so fish with this type of hook left in their mouth are less likely to survive. However, many fishing hooks today are made with a high carbon content, meaning that they will rust away when left in a fish’s mouth. While some fish will of course die due to hooks being left in their mouth, most anglers now agree that fish released with hooks still inside their mouth at least have a fighting chance of survival. Many anglers report catching fish with rusting and decaying hooks inside their mouths from previous times they have been caught, meaning that some fish released with hooks still inside of their mouths do go on to hunt and feed in a way which allows them to live.

Killing Fish Humanely

If fish are being kept for food or bait it is only right that they are killed quickly and humanely. A priest is a kind of club specially designed for fishing and is used to hit fish over the back of the head and kill them instantly, while small fish such as mackerel can be quickly killed by breaking their neck by bending the upper jaw all the way back as far as it will go. Smashing a fish’s head off a rock or a stone floor is not an effective way to kill fish and creates a horrible image of anglers to any members of the public passing by, and it is certainly not acceptable to simply leave fish out of the water until they suffocate to death.

Returning Fish to the Sea

When it comes to handling a fish, and returning it to the sea there are a few simple guidelines to follow that can reduce the stress the fish is under and increase its chances to live to fight another day. Try to keep handling fish to a minimum – hot hands shock coldwater fish and often it is believed this often kills them rather than any actual injuries. Species such as whiting are particularly susceptible to this.

An angler unhooks a pollock before returning it to the water.
An angler unhooks a pollock before returning it to the water.

Hopefully, it will be possible to grip the fish securely but gently and remove the hook from its mouth quickly. It is then simply a case of placing the unhooked fish back into the water, or dropping it from the lowest point possible if you are fishing from an elevated position. Some anglers (for reasons unknown) seem to delight in throwing or launching fish back into the sea. This is unnecessary and harmful to the fish and may well result in its death. If small fish are caught on a beach it is a good idea to gently place them past the breaking waves (if safe and possible), as small fish can lack the power to get past these waves and will simply wash back up on the shore.

Tope Photograph
These days many anglers are happy to get a photo of themselves with their catch and then return it to the sea.

If a fish is to be measured before returning it to the sea then do this as quickly as possible. In freshwater fishing landing or unhooking mats are often used to place fish on when they are being unhooked or measured, and there is no reason why these cannot be used in sea fishing to protect the fish from scrapes against rocks or a stone pier floor. Simple measures such as having the tape measure ready rather than spending time getting it out of the bottom of a tackle box can help minimise the time a fish is out of the water. Similarly, fish being weighed should be put in a bag or sling and weighed on scales that are ready for this purpose, and never hung by the gills. Today many anglers like to take photos of their catch, particularly if they have caught something unusual, rare or noteworthy. The ubiquity of digital cameras and smartphones has led to many more fish being returned alive as anglers can now easily take a quick, high-quality picture of their catch and then return it to the sea – in the past many fish were killed simply so anglers could get a photo at a later date as it was not practical to take cameras along on a fishing trip. Species such as smooth-hound (which have made a comeback in terms of numbers) are now fished for almost exclusively on a catch-and-release basis, and an angler killing smooth-hound on the shore would not have many friends amongst fellow anglers. The same is true with fishing for skate and boat fishing for shark species which is now done entirely on a catch-and-release basis. In recent years many anglers have effectively ceded British and IGFA world record catches by returning large fish which would have set a new record. This has led to the establishment of the Notable Fish List compiled by the British Record Fish Committee to register and record noteworthy fish which have been released by anglers instead of being killed in order to claim a new record.