How Well Can Fish See Or Hear Me?

Fish in general are not the smartest animals on the planet. However, they do a few things extremely well, like selecting food, finding good habitat and cover to feed from, and displaying an uncanny ability to flee from a perceived threat. You better believe that a fish can see you, feel you and hear you as you crash through streamside brush and make tromping and splashy footsteps through the water. In fact, trout specifically have lateral lines on their sides that enable them to feel motion and the direction it's coming from, far beyond the ability of a human to do so. This is why a trout may spook far away from you, even when you may feel like you are far enough away from it to avoid doing so.

What Traits Do Fish Have That Enable Them to Know I’m Here?

• The lateral line is the most important trait. A lateral line is made of a series of U-shaped tubes. When the water outside the U vibrates due to a sound, a hair at the base of the U sends a signal to the fish's brain. It is then translated by the fish as to the location of where the sound originated.
• Their eyes allow them to see threats coming from above very well. Their eye placement is crucial as well as the broad angle vision that helps them to see all movement that is occurring above them. The more clear and gentle the water is flowing above them, the better they can see you. As the water becomes faster and more turbulent, their ability to see becomes less and less great.
• Less important to the fishing aspect, but equally important to the traits of senses to a fish is their sense of smell. Because they can't breathe out of water, they can't smell you coming or anything like that, but once scents are in the water, fish use their impeccable sense of smell to find out what's in the water. This is why scented baits are so successful in catching fish.

What Can I Do to Avoid Being Seen or Heard?

This question is the crux of why any of this is important to anglers. Stealth, especially when stalking fish, fishing spring creeks, or fishing to rising fish, is crucial. When fish are rising, they are at their most vulnerable and therefore can be extremely wary of any movement and differences in their natural habitat. A lesson can be taken from competition fly anglers, who often wear kneepads because they will kneel in the water rather than stand, minimizing the ability of a fish to use their broad angle vision to spot you and spook.

• Slow down. When wading or approaching a fish that you've spotted, walk slowly upon your approach and use slow motions. Limit your casting to the bare minimum you need in order to make your presentation.
• Wear drab colors. Avoid wearing brightly colored clothing. Believe it or not, wearing clothing that stands out from the natural environment could allow a fish to more easily see you. There's no need to go full camouflage or anything, but stick to drab colors to avoid spooking a wary fish.
• Fish from your knees. The less of a profile you make available for fish to see, the less likely they are to spook by visually seeing you and the motion you create. When possible and faced with especially spooky fish, keep your profile low so you limit their ability to see you.
• Keep your distance. Stay as far away as possible from the fish as you present your flies. This may mean that you need to make an upstream presentation and cast well above the fish or it may mean that you need to stay on the bank to make a cast. Either way, try to stay as far as you can away from the fish, while still being able to present the fly in an effective manner.

Fish that are milling about in slow water or gin-clear side channels of a river are going to be far more wary than fish set up in a fast, diamond chop riffle. With this basic principle in mind, take extra caution when approaching fish in slow and glassy water. They can and will see you if you do not take care in your approach and your presentations to them. Once you're spotted and one fish spooks, they will send alarm bells to all the rest of the fish in the spot and your chances of catching a spooked fish are zero. This represents a challenge for sure, but nothing compares to fooling a fish that's one mistake away from spooking. Take your time, go slow, and you may be rewarded with a quality fish in return.