Catch and Release

 Catch and Release Techniques

Catch and release has been around for a long time and is now very widely adopted in many fisheries around the world, most famously in the USA and New Zealand but increasingly in countries that traditionally catch trout for the pot such as France, Spain and Italy, where ​‘no kill’ zones are now designated in some rivers. 

This page is intended to give a guide to best practice catch and release as well as some of the impacts.

Catch and release – the quick guide

  • Use barbless hooks

  • Bring the fish to the net as quickly as possible

  • Keep the fish in the water

  • Handle as little as possible, and always with wet hands

  • Do not squeeze – it damages internal organs

  • Remove the hook using forceps if necessary

  • Avoid contact with the bank or gravel as this removes protective slime

  • Release the fish by pointing its nose into the current so that water is flowing over its gills

  • Support it gently until it swims away

We found this video below to be a good summary of best practice catch and release:

 
 

Getting trout to the net

Use a net! For anything but very small fish, a net is the most effective way to perform catch and release with minimum damage to the trout. 

The objective is to get the fish to the net and back into the water as quickly as possible to maximise its chances of survival. Evidence shows that a prolonged ​‘fight’ increases the stress on the fish and reduces its chance of survival, especially if water temperatures are high (see below for more on this).

Use tackle appropriate for the situation and the size of fish you expect so that you can land the fish quickly. A 3 or 4 weight rod and very fine tippet is perfectly good for small wild trout, but many rivers like the Madison hold larger wild fish and have swift currents and for this you need a setup that allows you to control the fish and bring it to the net quickly. A 5-6 weight rod and 3-4X tippet is a good starting point. 

Don’t have a tug of war. Learn how to throw the fish off balance by moving the rod left and right to create side strain. Bring the fish into slack water to net it. 

The effect of temperature

Trout are cold water fish and prefer water temperatures hovering around 52 degrees F. The amount of oxygen in the water declines as water temperature increases, which means that being caught and landed is far more stressful for trout as water temperatures rise, and the chances of survival reduce. 

During warm summers with low flows, especially in rivers with little shade, water temperatures can quickly become too high for survival following catch and release. It is the water temperature not the air temperature that matters. A nice cool summer evening for fishing for you may still be a lethal water temperature for the trout, so take the temperature of the water before you fish.

Barbless hooks

These are much easier to remove quickly than barbed hooks, and a synthesis of research carried out by the Environment Agency on salmon catch and release showed that they caused less damage to the fish. As an added bonus, they are also much easier to remove from your finger, net, hat or trees! Barbless hooks are now very widely available for fly tiers and barbless flies are often readily available at your fly shop. If not, you can “pinch” the barb down using a pair of hemostats.

Will you lose more fish if you use barbless flies? Inevitably opinions vary but many very experienced anglers will say ​‘no’.

Nets

Using a net is the easiest way to minimize handling the fish (and removing slime) and keeping the trout in the water while you remove the hook. However, old fashioned nets can damage trout. Knotted string or nylon nets have been banned in many areas because of the damage they cause to scales, tails and fins. The best nets have a fairly fine rubber mesh. They have the added advantage that they dry quickly, as easy to disinfect and don’t smell!

If you are wading, hold the handle of the net between your knees whilst you remove the hook.

If you are fishing from the bank or boat, make sure your net has a long enough handle for you to be able to reach down into the water to net the fish. Keep the net and the fish in the water while you reach down to remove the hook. Don’t lift the net and fish onto the bank or into the boat.

Rubber mesh landing nets prevent damage to fins and tail

Removing hooks

You will need to carry forceps, hemostats (or some form of release tool) and it is good to get into the habit of assuming you will always need them. Have them in your hand as soon as the trout is in the net. 

Don’t squeeze the body of the trout in order to remove the hook. If the fish is thrashing, cradle it belly up in the net while you remove the hook. If you cannot remove the hook quickly (for example if it is the throat of the fish), cut the leader close to the hook and leave the hook behind. It will work its way out and is likely to cause less damage than a prolonged wrestling match. 

Holding trout for photos 

Cradle the trout just behind the head and hold the wrist of the tail firmly. Keep the trout in the water for as long as possible, lifting it out very briefly to just above the water to take the shot. Always support larger trout with two hands.

Holding a live trout for a photo can be tricky (especially if it is a big trout) and it is tempting to squeeze the fish to get a good grip. However, you could be inadvertently killing a fish that you are planning to release, because the place where most people will hold and squeeze a fish – just behind the head – is where the heart and liver are located. A fish subjected to squeezing of the heart may swim away but die soon after. 

For large fish, it is also important to support the fish so that the back isn’t sagging. Supporting the fish at the vent and the pectoral fins is the best way to achieve this. Those points generally do not indent and put pressure on the internal organs because of the skeletal and musculature structure.

How long should it be out of the water? Ideally less than 10 seconds, certainly not minutes – if water stops dripping off the fish, it’s too long. If you need another shot, put it back into the net in the water to recover for a minute or two and try again.

Proper way to hold a trout for a quick photo:

Letting it go

Point the nose of the fish into the current so that water is flowing over its gills. You need a reasonable flow but not a torrent, and clear water, not water full of sediment. If you have done a really good job, the fish will instantly kick away. If the trout is stressed, it may take a minute or two to recover before swimming off. Hold the trout gently in the water until it moves off. 


Do not move it backwards and forwards. Water needs to flow through the mouth and out over the gills for the fish to breathe. The unnatural backwards movement pushes the delicate gill lamellae in the wrong direction and hinders their breathing, potentially damaging the gill, causing additional stress and prompting the fish to swim away before it is actually ready.

A summary of things to avoid: 

  • Holding the trout out of the water for more than a 10 seconds. A gasping trout is ​‘drowning’ in air.

  • Laying the trout on grass or shingle or any surface away from the water. Trout are covered with slime which protects them from disease, particularly fungal infections, and contact with surfaces (including rough nets) will remove slime.

  • Touching the trout with hot, dry hands as this will also remove slime. Wet your hands before handling.

  • Don’t squeeze the trout or get your fingers near or in the gills.

  • Don’t have a wrestling match to remove the hook. Barbless hooks should come out easily but if you can’t easily remove it then cut the leader close to the hook and leave the hook in place. The hook will come out naturally in time and this is better than squeezing the trout and holding it out of the water.

More information

The Keep ​Fish Wet website is a very good source of information about catch and release for all fish species.