It seems easy but so many get it wrong. Peter Cockwill guides you through this vital part of our sport...
You would think that netting a trout was simple, but I’ve seen huge blunders resulting in lost fish of a lifetime! So here’s the Trout Fisherman quick fire guide to getting the job done properly.
1 Make sure you have a net close to hand.
It’s all too easy to forget your net or to leave it somewhere along the bank where you can’t get to it in the heat of the moment. So have it by your side.
2 Is the net up to the job expected of it?
All I have in the picture (below) is a small, river angler’s net. The handle is too short and I’ve really struggled to squeeze this eight-pounder into it. This was a disaster just waiting to happen.
3 Is the fish actually ready to be netted?
It’s very clear in this shot that the trout has loads of energy left and I’m in real danger of breaking the leader if I try to bundle the fish in before it’s ready.
4 Have you got the net in the right position?
You should have the net rim under the water surface and be stretching out to the played-out fish with enough movement left to be able to push the outer rim of the net upwards to make the fish fall into the bag of the net.
5 Is the net big enough and strong enough for the size of fish you intend to catch?
Some nets have really strong handles and can lift a considerable weight, but the majority are made to be lightweight and easy to carry.
Don’t lift your net by the end of the handle, instead you must either support the handle along its length or lift it with the handle held upright so that the fish weight is carried by the net itself.
Landing nets come in a great many designs but the actual frames are either solid or collapsible and here’s where you need to make your first decision when choosing a net.
Construction of nets varies from steel to aluminium to plastic to reinforced carbon fibre. Here you have to decide if weight is an issue.
Maybe you always fish from the same place and rarely wander the banks.
In this case a solid, well made net may best and it will last for ever.
Most nets are made of aluminium, either solid rods, hollow round tubing or hollow angled tubing.
The latter are actually the stronger and lighter plus some designs can be very tough indeed. The heavier, solid rod designs are also very dependable.
Plastic nets are often a mix of thin aluminium rods and lightweight plastics with the almost inevitable consequence that they will fail at the critical moment of netting a trophy fish. But if economy or infrequent need are the deciding factors then appreciate the restrictions.
Nets made from reinforced carbon fibre and lightweight alloys are remarkable value but can’t be expected to be as strong as all metal constructions, although as a beginners or standby option they are fine.
The final option is whether the net has an extendable handle. If your chosen fishery has high banks, extensive marginal reeds or shallows then you need to reach out and the telescopic handles are ideal. Older or disabled anglers can’t bend down too easily and will need this type of net.
If a longer net is needed then consider some of the coarse fisherman’s style of net with a carbon fibre telescopic handle and a screw in net frame. They’re not so easy to carry but great if you need a super long handle.
FOR It’s much easier to tip the forward edge of the net upwards to engulf the fish and make sure it is tipped into the bag of the net.
AGAINST It needs space to be carried and stored.
FOR It folds down into a compact size
AGAINST It can be all too easy to tip a fish out of the net such that the hook comes free or the leader breaks.
In most fisheries, whether stillwater or rivers, there’s likely to be a mixture of recently stocked fish and those which have survived since being stocked a few seasons ago. In a commercial fishery the former will be by far the most abundant.
Overwintered fish would have adapted to their new environment to survive as well as avoided being caught or eaten by a predator. There are some general rules for telling fresh stockies and overwintered trout apart.
FRESHLY STOCKED TROUT
Freshly stocked fish are at their highest risk of being caught. Studies show that over 95% disappear either through being caught, death through natural causes or predation. These naïve stockies are generally active and least wary. They’ve been in an environment that conditions them to compete actively for food. This means they will have a go at pretty much anything that resembles food.
Scientific studies show they feed poorly for the first few months as they are unaware of the value of many natural foods or how to catch them. This lack of feeding is less of a consequence than for humans, fish can survive without food for more than six months at a push, and this gives them a long time to find food. They will learn to find food in their new environment but as they are establishing these skills they are most likely to be caught.
They’ll gradually become more wary, not just of anglers but of other potential predators. If they don’t they get caught and removed. Stocked fish can therefore be identified by their behaviour, they move around the fishery “exploring”. These fish are less likely to establish themselves in an area where overwintered fish are present. They will also be less wary of potential hazards such as anglers! Those few fish that don’t get caught or eaten will become semi–wild. Next season, they’ll present a more challenging quarry as they are wary of perceived danger and therefore have less chance of being caught compared to fresh stockies.
TELL THE DIFFERENCE
During their time in the fishery these overwintered fish will have undergone physical as well as behavioural changes. It is these physical changes that we can often use to identify them from the recently stocked fish.
Newly stocked fish will have been fed on a diet of trout pellets and grown at a commercial rate to ensure they meet market size requirements. In doing this the energy intake of these fish (i.e. fuel in the form of food) will have been more than they need to grow muscle, and the excess nutrients particularly fat will be stored in the muscle tissue and viscera (a thin layer of flesh).
Stocked fish often look fatter in the body than wild fish. This isn’t extra muscle but the body cavity and muscles filled with excess fat. This is particularly pronounced around the abdomen, the fish often looking “plumper”. An overwintered fish will look much more slender.
This extra fat isn’t as much of a problem to a trout as it would be to a human. Trout are able to use these fat reserves very effectively. In fact they use fat as the main source of energy, unlike humans that tend to use carbohydrates for this. A normal rainbow trout is capable of eating and growing well on food with a fat content in excess of 25 per cent. If we tried that it would kill us off in a matter of weeks!
One of the problems of all this fat is that it can interfere with muscle function so it’s no surprise that these trout don’t fight as well as leaner fish. The fat is used to power the muscles but it interferes with their ability to contract effectively and supply sufficient energy long term.
An overwintered fish has lost all this puppy fat with a long period of poor feeding and then living off natural foods with lower fat contents than trout food in farms. They will also have had to become far more active to survive and so generally are a fitter, leaner animal.
This is usually obvious once hooked, both give an initially good performance but the stocked fish is more likely to tire quickly and also be far less aware of potential snags.
THE FLESH AND BODY CAVITY
The eating qualities of the two are also very different, the lack of fat in an overwintered fish means that it retains less moisture when cooked and is therefore dryer.
The flesh firmness is also different with the recently stocked fish having softer flesh. The body cavity and viscera of a recently stocked fish are generally much fattier than with overwintered.
The stomach and pyloric caecae (finger-like projections around the stomach) are generally embedded in fat. Wild or overwintered fish rarely have sufficient food to lay down this much fat and so the u-shaped stomach and pyloric caecae are easily distinguished in the viscera.
The skin pigmentation may be used to identify overwintered fish. These often have well-defined spots and strong skin pigmentation, which is less defined in farmed fish. The pigment in the skin is vital in wild fish for camouflage, they also experience a wide variety of light levels in the wild. On a farm the light is more constant and so they tend to have less well-developed skins to enable changes in colour.
The colour of the flesh is influenced by whether the fish has eaten the required pigments to turn the flesh pink (below left).
This can be in the food fed on the farm or in eating a lot of shrimps in the wild, either way the chemicals are pretty much the same thing.
Trout that have been in a fishery some time will have a more varied diet with regard to pigment content so the flesh is generally much less pigmented as the pigment in the muscle gets used up in eggs and the skin (below right). But, trout in habitats where shrimps are not a major part of their diet will have white flesh, just like farmed trout fed on food without the pigment.
FINS AND TAIL
Body condition, particularly the fins, can be used to determine whether a fish is freshly stocked.
The fins of farmed fish are much more prone to erosion and damage; some table farmed fish can erode some fins completely. This damage will be most pronounced at the edge so look for fraying and a white edge, which is damaged skin. This is particularly noticeable on the dorsal fins of trout. It is quite difficult for a farm to get really good dorsal fin quality prior to stocking.
The other most common damage is splitting. This is common on farmed fish but much less so in trout that have been in a fishery for a while, as splits repair and are less likely to happen.
The tail or caudal fin is another good indicator. A clear, well-defined tail is usual in wild or overwintered fish. It will have clearly defined points at the tips, generally missing on a recently stocked fish. A wild fish is highly dependent on its fins for survival and so they are much less susceptible to damage. The fins will re-grow over time so an overwintered fish is likely to have relatively good quality fins.
Some fin damage can take a long time to re-grow and severely damaged fins may remain stumps.
Stocked fish generally have good quality fins compared to table farmed fish, and the relative damage they suffer depends on the type of system they are grown in.
This demand for increased fin quality means the prices paid for stocking quality trout are much higher as the farm has to grow them on in less economic systems at much lower stocking densities. This ensures that the fin quality of the fish is much higher.
AT A GLANCE...
FRESHLY STOCKED RAINBOW
1 Intensely farmed trout will often have ragged or split tails and fins due to tail-nipping by other fish, rubbing against concrete raceways and handling through grading. From fingerling to stocking, a fish may be graded three or four times
2 Greater fat deposits in the muscle restrict contraction
3 Pale skin colour
4 Fatty body cavity with various organs less defined
5 Pink flesh as some food pellets contain dye to make the flesh more attractive
WILD BROWN TROUT
1 The freedom to swim in open water allows fin damage to repair helping full fins and sharp tails to develop
2 Muscle is leaner and therefore fish fight hard for longer periods
3 Skin colour is more pronounced and defined to aid camouflage
4 Hardly any fat in the body cavity means all organs are easily distinguished
5 Wild trout only have pink flesh when their diet is mainly shrimp-based. Otherwise flesh is pale, almost white
The reason for spooning a fish is to find out what insects it has been feeding on so you can then select an appropriate pattern to imitate the naturals.
Bear in mind that if the contents have been in the trout’s stomach for some time they will have started to break down and probably be completely unrecognisable. But if the trout has eaten quite recently you should be able to recognise such things as buzzers and nymphs, and if they are still alive maybe even identify their actual colour.
The tool used for this task is called a marrow spoon, available either as a combination priest/marrow spoon or a separate instrument.
Only spoon a dead fish – you wouldn’t believe some of the things I used to see in my time running fisheries and yes, one of them was someone trying to shove a marrow spoon down the gullet of a live fish!
When you have retrieved the spoon from the trout’s stomach the contents at the very tip of the spoon will be those that have been in there the longest, and probably the most unrecognisable. In the middle will be semi-digested insects, but still worth imitating, and finally the contents nearest the handle will be its most recent meal – and probably the easiest to identify.
Have you ever wondered what brown trout and rainbow trout can see under the water? Knowing this information can make fishing for trout a whole lot easier, that's for sure!
Even though vision and the eyes of trout have been studied intensively over the last 60 years, we will never actually know for sure what a fish sees. But we can make a reasonable guess as to what they are seeing.
Trout are like many anglers, heavily reliant on their visual sense. They rely on it to move around, spot and capture food or escape predators. For trout, sight is possibly their most important sense. In many ways their eyes are very similar to the way our own work, although a trout’s eyes have to work under very different conditions to ours, and so there are significant differences.
To get an idea of the difference, anyone who has tried to see underwater unaided will know that our eyes aren’t up to the job. In fact, we become very long sighted when trying to see underwater, so trapping an air space in front of our eyes (in a mask or goggles) is required to see anything clearly. Living and being able to see underwater presents a whole load of different problems to living in air.
Being able to see something requires light to enter the eyes and hit the sensory surface (retina) at the back of the eye, that’s the same for fish and us.
A major factor for fish, however, is that most of the light hitting a river, lake or pond is reflected straight back into the air; only a fraction actually passes through the surface into the water. This light doesn’t travel well through water with many of the colours absorbed or disappearing, as you get deeper.
This is significant for fish as the colours they see are dependant on what light colours are available in the water. This means that trout, like most fish, have eyes that are set up to work in low light conditions, even during the day. So trout eyes have large pupils that let in as much light as possible - the iris, which forms the pupil, will not expand or contract like our iris during changing light conditions.
Trout do have a way of adapting their eyes to bright or duller light conditions but it can take hours not fractions of a second like our eyes.
The location of the eyes in trout means that they maximise their field of vision. To enhance this they push the lens through the pupil so light can enter the eye more easily. Look close, you can often see the protruding lens. A trout can see all around rather than just in front, with only two small blind spots, one just in front of the nose and the other behind its tail.
Trout don’t have the good binocular vision we have. This is when both eyes can see an object at the same time, it allows the brain to gauge distances quite accurately, explaining why we are all such pinpoint casters! A trout sees best in front and above the head.
To see clearly underwater, a trout has to focus an image of an object on to the back of its eye much like we do when using binoculars. The critical part of the eye that does this job, just like binoculars, is the lens. To get a clear image, the light has to be bent to focus the image onto the retina.
To do this well underwater is a problem, and when light travels from air to water it bends, so when you try to grab an object underwater it’s never where it actually seems to be.
Human eyes rely on this light bending to work. Fish in water don’t have this advantage so their lenses have to do all the work in focusing the image on the back of the eye.
To do this they use spherical lenses. They look like little clear glass marbles but provide perfect focussing irrespective of which part of the lens the light travels through.
Trout have exceptionally good lenses, much better than most fish, so their peripheral vision is excellent. This wide angle of vision means they can spot prey or predators easily. The downside is that, if the fish is out of water, it’s as short sighted as Mr Magoo! There is no danger of a fish seeing an angler as it jumps out of water, not unless it hits him.
To be able to adjust its eyes to see near and far objects the entire lens is moved rather than changing the shape as in humans. However a trout’s eyes generally don’t need to see very far as visibility in freshwater is often less than 10ft. So a trout’s eyes are set up to see things that are quite close.
Their eyes don’t have the features we have that allow us to see real detail. This has benefits for anglers, as it goes some way to explain the success of flies that mimic natural food.
These don’t have to be absolutely perfect replicas of the original. If they’re the right shape, size and colour the fish will have difficulty telling the difference.
Possibly more important is that the fly imitates the natural movement of the prey.
Trout see silhouettes of objects and pick up movement well, rather than intricate detail.
What trout see through the water surface is often a matter of debate for anglers. Trout, like most fish, can see the world above the water as a circular window above their heads.
The location of the eyes means that they can actually see all around in this window. Beyond this window the water surface looks like a mirror and so they see a reflection of the river/lake bed.
Within this window however, because of the old light water bending trick, they can actually see more than just straight above their heads. They can see about 10° above the horizon.
So, an angler standing on the bank is usually very visible. You must crouch down or get in the water to reduce the angle so you’re not easily spotted. A fish high-up in the water is more likely to see an angler than one deeper down due to the reduction of the window above their heads.
Trout, like most fish, can see in colour, and they have the right receptors to see the full range of colour we do; as fry they can also see UV light, losing this as they age.
Migratory trout regain UV light perception on returning from the sea. They also detect polarised light, which tells them when dawn and dusk are happening and stops them confusing that with changes in cloud cover. Their eyes are tuned particularly to green and orange light, the most common in freshwater.
When you compare the most common light colours present in water with those the trout is set up to see, there is often a slight difference. This allows trout to see reflective objects in water; they are seen in silhouette by the fish. This means that the camouflaging effect of the silvery scales of small fish isn’t very effective against trout.
DIAGRAM OF A TROUT'S EYE
The outer protective layer is tough, the inner contains dark pigment which helps make the eyeball light-proof from behind. The suspensory ligament and retractor muscle hold the lens in position and the muscle moves the lens when focusing. The falciform process probably has a nutritive function.
To be able to see something, light must enter the eye and hit the retina at the back.
A trout’s large pupils absorb as much light as possible in the low light conditions under the water.
THE TROUT'S BLIND SPOTS
Trout can see all around them, and not just in front, with only two small blind spots – just in front of the nose and behind its tail. Given that they see best in front of and just above the head, it’s clear where anglers should cast their flies.
● Trout leaping free of the water can’t see you.
● Trout see things clearly that are quite close.
● Their eyes don’t have the features that allow us to see real detail. So flies don’t have to be absolutely perfect replicas of the original, if they’re the right shape, size and colour then the fish will have difficulty telling the difference. Possibly more important is that the fly imitates the natural movement of the prey. Trout see silhouettes of objects and pick up movement well rather than intricate detail.
● In real terms then an angler standing on the bank-side is usually very visible. Avoid being spotted by crouching down low to the ground or get in the water to reduce the angle. A fish high up in the water is far more likely to see an angler than one deeper down because of the reduction of the window above their heads.
For more information on the different trout species, click HERE.