Colour & Light | Rob Hughes


Some will have you believe that colour doesn’t make the slightest difference, and that carp can’t see colour anyway. Others will be convinced that yellow bait is the key, or red is the one. Whatever your opinion, there is no doubt that, sometimes, certain colours will out-fish others, and that alone is sufficient evidence that colour matters. 

As you probably know, I’ve spent a lot of time underwater, and looked at loads of different colours and how they react in different light and different situations. I’ve also heard an awful lot of ‘barstool expertise’ about what is and isn’t the situation with colours. What I can say from my experience, is that some colours seem to catch me more fish. There have been numerous times when using certain colours has made all the difference, or has brought a bite that I wouldn’t have got without the change, but it goes much deeper than that. 

The Carp

The first thing I want to look at is the carp itself. What can it see? After all, it doesn’t really matter what we see, it’s what and how they see that is of the greatest importance. We know that carp are dirty-water-dwellers in the main, and know they have a sense of smell. It goes without saying that they can use both their eyes and their noses to locate food. They can also taste it. Additionally, they use their eyes and their lateral senses to warn them of danger, and their sense of hearing to notify them of both. But how do they see?


For a start, it’s fairly well known that they can focus on objects, detect movement, and differentiate contrast, and this is where camouflage and concealment of rigs come into play, but more of that in a different feature. There are also a lot of answers in nature itself. In fact, I’m of the opinion that nature has the answer to almost everything. We either haven’t found it yet or don’t see it. 

A practical example of whether fish can see colour is solved by looking at the fish themselves. It’s no surprise that most midwater fish are silver-sided; light from below and dark from above, and predators such as pike and perch are green. That tells us an awful lot about how fish see. In addition, the only fish which has really been ‘interfered with’ in our waters is the carp through selective breeding, which is obvious underwater (commons excepted) because they don’t have a natural pattern any more. 

It’s believed that carp are pretty short-sighted, i.e. they cannot see long distances, and rely primarily on their sense of smell. However, having watched literally hundreds of them underwater, nothing will convince me that when a fish is relatively close to the bait, it doesn’t use sight to locate it, with smell as a secondary system. They look for food with their eyes. Simple as! The Korda underwater footage of the fish homing in on a particular-coloured bait sort of backs this up, although I appreciate that there are flavours involved as well. 


Polarised Light

Something that has pricked my interest recently is polarised light. This is light which is effectively seen on one plane, e.g. linear, as opposed to its usual state of bouncing around, e.g. circular. Light underwater, especially in turbid water, is bounced off many surfaces, such as suspended solids like algae, or light suspended silt. It’s thought but not fully proven that some fish have polarised vision, which is effectively the same as when we wear polarising shades. 

So why does this matter? Well, if the early evidence is correct, and it’s only early evidence, it means they can see through dirty water a bit easier than we think. The ‘scatter’, as it’s known in underwater circles, or glare, as we usually call it, is taken out. It also allows them to pick out objects against a dirty background, a little bit like wearing 3D glasses. This is probably why Zigs are so effective. 

The final thing that’s important is their ability to differentiate between contrast. Standard military camo and concealment rules apply. If you don’t want to stand out, match yourself to the background, as a silhouette is a massive giveaway. Shadowing and vastly different contrasting colours together stand out like a sore thumb. Sometimes this can be a good thing, other times a bad one, depending on what you are trying to achieve. Remember that when you look laterally underwater, the dominant colour is green or lightish-brown. 


Water – a Bit of Science

When light hits water, it does a number of things. Some of it reflects off the surface and doesn’t penetrate water at all, and the light that does gets refracted. This simply means it bends a little, due to the difference between air and water. We don’t need to worry about that unless we are trying to hide from them, in which case, be stealthy and get your head down! The key thing is that it does get weaker and changes colour. This is called attenuation, and this is the bit we are particularly interested in. 

Attenuation is caused by two things: scatter and absorption. Light rays are basically just that – millions of individual rays that try to travel as far as they can. Things in the way above water, such as the atmosphere, clouds, rain, and things that cause shadows all knock light rays around a bit and weaken them. Water is another one, so when the light we see travels into water, it changes again, and filters out the colour. Think about a clear day when the light is bright, or a grey cloudy day when the light is dark. This is the same effect underwater. There’s also colour filtration to think about. 

Saltwater is blue when viewed from below, as it filters the sun’s UV rays (blue), and the salt in it bounces the light around to make it appear blue. Freshwater tends to be green because of all the algae suspended in it. That’s why when sea-fishing, a clear or blue line is less visible, and freshwater lines tend to be green. 


For a colour to show up, it needs to be hit by the same-coloured light, and this is where I must bust a long-standing myth. Red is not invisible underwater. I’ve seen loads of reports in fishing mags and on the Net that all say the same thing. It’s not invisible, it simply changes colour, and the depth at which this happens depends on several things, especially whether the water is salt or fresh.

In fact, I’m looking at a feature that states: ‘at a depth of 10ft, a red fly appears grey’. Not in freshwater it doesn’t. That’s simply not the case. In blue water (salt) it happens at depth, and at 30ft there is little or no red light. It’s different in freshwater because of the green filtration of the algae and suspended solid. Red is visible in shallower water; in deeper water, e.g. 30ft+, red looks green.

Remember guys, if red was so invisible, why are red maggots so effective? Why do red boilies stand out so much? And why do people write such drivel?

Fluoro Baits

Fluoro, as opposed to simply bright baits, act slightly different in light because they tend to ‘grab’ ultraviolet light rays, which makes them stand out more. In lower light conditions, this can be a real advantage because UV is the dominant light on grey days. Fish can pick out the bait more easily, and this is probably the scientific reason for fluoros being such a popular and successful winter bait. 

UV light is at the blue end of the spectrum. Its light waves are shorter than the red end, and invisible to us, so they tend to travel further than red light. They react with a fluoro bait and make the bait stand out. On bright sunny days, the fluorescent effect is reduced because ‘normal’ light reduces the UV effect on a fluoro, and if there is no light at all, then there will be no fluoro effect. 

A practical application for this might be to use a fluoro bait in the daytime if it’s grey, and then change over to a white bait or a very smelly one for the night-time. If it’s bright, use a vivid red one in shallow water, or a yellow or white one if you want the bait to stand out in deeper water. 


Daily Colour Changes

One of the things rarely mentioned is the way light changes through the course of the day, and how that can affect the way the bait looks and how fish see. If you take photographs, you’ll know that the light in the middle of the day is harsh bright and blue, and at each end it has more red in it. In fact, dawns and dusks are slightly different too, with more orange/red light at the end of the day than at the beginning.

I’ve been taking photographs underwater when a cloud has blocked the sun, and the bottom changes significantly and looks completely different. Even more important are areas which come into shadow part-way through the day. They are massively different to the brighter areas in the pond, and while I’m talking more about light than colour here, it has a big effect on the bait and how it can be seen. 


I’ll put all this scientific conjecture into context. I must make it clear that I’m no scientist, but I have an interest in science, especially applied science, and when a little bit of thought is given to adding two and two together, four is a pretty obvious answer. That’s effectively the extent of my scientific background. However, I do have a massive amount of practical experience, both through fishing and diving for so many years.


All the stuff I’ve written is important if you want to understand how and why light affects the fish and the baits you use. I always feel that if you can understand why something is working, then you can fix it when it’s not, so here are a few practical examples of light and colour that may well be applicable to where you are fishing. 

I’ve seen that white in bright conditions, e.g. clear and shallow water, is really bright. It also stands out well in deeper, darker and murkier conditions, especially deep clear water. In
midwater, say between 6 and 30ft, it is an average colour. 

Yellow is brilliant as a very deep-water bait. Anything at the red end of the spectrum tends to lose its colour a bit more. I can remember fishing in the very clear water of the St Laurence, at 40-45ft, a few years ago, and I rarely got a bite on orange baits, but yellow ones worked very well. The fish were clearly sight-feeding and could see yellow, whereas the orange ones lost their colour.

Dark baits aren’t necessarily camo baits. I’ve seen a lot of light-coloured silty bottoms and a dark bait, especially a red one, and it really stands out on the deck if the silt is light. There are a lot of situations where people use something for a reason, when in fact it’s the opposite reason that makes it successful, and red feed baits on the deck are a prime example. 

Hi-vis Yellow – Really?

One of the things I touched on earlier was camo and concealment, and the best way to hide something in sight is to make it the same shape and colour as the things around it. 

A lot of anglers think that using a yellow bait means they are using a standout bait, but in certain situations, nothing could be further from the truth. If you look laterally across water from underneath the surface, it is greeny-yellow. Weed tends to have green leaves, and the underneath of the leaves and the stems are yellow. Silt is also a lot lighter than we perceive, so there is a lot of greeny-yellow stuff underwater. I know from my own experience that yellow baits are a lot harder to find than red ones. 



For me, the most visible colour underwater is pink, be it a washed-out pastel pink or a vivid bright one. There simply isn’t anything like pink underwater, so they stand out a mile. Orange and red are close seconds, with red edging it for me as a favourite, but as a hookbait, pink is a winner at almost all depths. There’s little wonder that so many fish get caught on pink baits.

If you want a really standout bait, have a look at the DNA Wraysberries Wafters. They are an incredibly vivid red colour that simply jumps out of the water. If you’re after sight-feeders, then this is about as good as it gets, and I’ve caught shedloads of fish in both clear and coloured water on them.


1.Always think about the colour underwater, not above it.

2. Fluoro pink is almost always the most visible colour underwater. 

3. Fish can see colours, but also rely heavily on olfactory senses.


Colour Chart

Something to bear in mind is the difference between colours. This is a colour chart which shows the relationship between colours. You’ll see that green and yellow are on one side, and red/orange on the other; they are directly opposite colours. Some colours complement each other, others clash, but this chart shows why red and orange work well if the colour of the water is green. Remember what I said about yellow; it’s right by the side of green, so they are very close to each other. You’re probably catching because it’s harder to see, not easier.

Grey matter time! 

FeatureMick Cliffordsecond