Can Fish See In The Dark | What Is A Lateral Line?

One of the most common questions amongst anglers is whether fish can see in the dark. If you have ever been night fishing, you may have hoped that you will have more success as there could be a chance that the fish won’t see you coming. Alternatively, your chances of a fish may be scuppered if they cannot see your bait.
But fishing aside, understanding these creatures is something that non-anglers take an interest in. There are more than 33,000 species of fish and humans have interacted with many of them for millions of years. For this reason, it’s good to know a little about them.
In this article, we are going to be answering the question of can fish see in the dark and looking at how this will affect your angling efforts.
How do Fish See in the Dark?
With fish inhabiting every corner of the planet, they need to have developed ways of surviving. One of these ways is by being able to see at night. But their version of seeing is vastly different from how we navigate through the dark.
So, if fish don’t use their eyes to see in the dark, what do they use? Fish have two rows of sensory organs that run the length of the body on either side. These are called lateral lines and they help the fish to sense when there are subtle changes in pressure in the water. These subtle changes could be an approaching predator, another fish of the same species, an angler or simply an obstruction in their swimming path.
There are other fish, such as eels and sharks that use special senses to detect changes in electric fields in the water. This signals to them when other creatures are nearby. It is important to point out that fish have very good vision during the day. According to science, the eyes of a fish are very similar to that of a human, in the way that they work. But to aid them underwater, fish have special adaptations like a protective film.
As night falls, fish are often left in complete darkness; there are some species of deep-sea fish that will never see sunlight and live in a blackened world for their entire lives. Some fish are prey animals and need to be able to sense when something bigger is stalking them. In contrast, other fish, like sharks, pike, and Arowana, for example, need to use their vision and other sense to catch a meal.
Can Fish Find Their Way in the Darkness?
Furthermore, when the lights go out, fish need to be able to move around the water without bumping into anything. It stands to reason then, that they can see in the dark.
However, as we have mentioned, while fish can find their way around in the darkness, they don’t necessarily use their eyes. Some fish, like those that live in the deep ocean, have extremely poor vision. But it is unlikely that any angler would ever come into contact with something that lives 7000 metres under the sea.
Fishing at Night
If you’re a nature enthusiast, learning about a fish’s physiology may be enough but if you’re big into angling then you will likely want to know how a fish’s nighttime abilities will affect your chances of getting a bite.
Ask anyone who has ever been night fishing and they will tell you that it takes much more skill and patience than hitting the water during the day. But that doesn’t mean that it is impossible; there are plenty of people who successfully catch fish at night. It simply requires a slightly different approach.
Conclusion
Fish have very good vision when it is light but when the sun goes down and things get dark, it can be difficult for the fish to see.
However, these animals are equipped with sensory organs along the sides of their bodies that pick up on subtle changes in the water allowing them to sense when there is a predator, food, or an obstruction nearby.
Frequently Asked Questions
Do fish have good eyesight?
Yes, in general fish do have good eyesight. They also have sensors running along their lateral line that can pick up on the slightest of vibrations in low light.
Can fish see in colour?
The short answer is yes, fish can see in colour. But not all species of fish can see colour as well as others due to their habitat. Fish that live deep in the ocean for instance don’t really have a need for seeing in colour.
How do fish hunt at night?
Generally fish can and will use eyesight to hunt in the daytime. At night when the eyes can’t see so well, they will use the sensors on their lateral line to pick up on vibrations from their prey.