What Do Trout Eat?

This post was last updated on July 8th, 2021 at 04:58 pm

What Do Trout Eat – Trout Foods and Feeding Habits

If you’re reading this article, you must be asking what do trout eat? Most trout eat mainly aquatic insects, but some larger fish rely on cannibalism to survive. Once a trout reaches a certain size it is less practical for them to eat small insects, the best way to consume a large amount of calories quickly is to eat other fish and other large prey such as crawdads and mice.

Sent wing mayflies after breeding will make easy pickins for trout. what do trout eat, what do trout like to eat, what do rainbow trout eat, what do lake trout eat, what do brown trout eatThese mayflies will make an easy meal for trout.

Aquatic Insects

Mayflies make up a large part of the trout's diet. what do trout eat, what do trout like to eat, what do rainbow trout eat, what do lake trout eat, what do brown trout eat
Mayflies and mayfly nymphs make up a large part of the trout’s diet.

Some of the typical insects eaten by trout are caddis, mayflies and terrestrial insects such as ants and grasshoppers. The larval stage of aquatic insects make up most of the trout’s diet. It is said that 90% of feeding takes place under the surface of the water. Since most of the life of these insects is spent underwater in the nymph stage, it makes perfect sense that that is where most feeding takes place.

A stonefly nymph crawling on a rck, what do trout eat, what do trout like to eat, what do rainbow trout eat, what do lake trout eat, what do brown trout eat
Nymph such as this stonefly are common foods for trout.

Baitfish and Sculpins


Sculpins can be found in most bodies of water where trout are found. They are small bottom feeding fish that live around rocky areas.


These small fish are frequently found in trout streams and are eaten by trout. There are dozens of species of chubs and they are found throughout the US in nearly every river and creek that contains trout.

A large trout feeding on insects in shallow water, what do trout eat, what do trout like to eat, what do rainbow trout eat, what do lake trout eat, what do brown trout eat

Feeding Habits

Trout will always try to expend the least amount of energy possible while feeding. This can easily be witnessed by watching a large trout eat. A bigger fish gets big by consuming more calories than it expends eating and catching food.

By watching a large fish feed you can see that it will usually sit in shallow water where it does not have to move more than a few inches to come up to the surface to eat an insect. It will also move very slowly and barely make any commotion on the waters surface, while a smaller less mature trout will often make a large splash and waste energy while feeding. Large fish will not live long if they cannot learn to eat and hunt food efficiently.

Trout Cannibalism

Perhaps the quickest way for a big trout to eat it’s daily caloric needs is to eat another trout. You will rarely see a big fish attack a healthy smaller fish because they are too hard to catch. But if a baitfish or smaller trout is injured and calling attention to itself, it will likely become a target. This is another instance where a trout will not waste energy trying to catch a fish that it know it will not likely catch easily.

Many of us have witnessed large fish trying to catch smaller fish after we have hooked them. I have seen several large trout rip a smaller trout right off of a fisherman’s line. The fighting of the smaller trout is enough to convince a large fish that it is an easy target and worth the expenditure of the energy.

What Do Rainbow Trout Eat?

The rainbow trout eats primarily invertebrate larvae, insects and other fish.

What Do Lake Trout Eat?

Lake Trout like to eat other smaller fish and sometimes take crustaceans, terrestrial insects, plankton, even small birds and mammals. They like to feed at night and also prey on bullhead, perch, trout, smallmouth bass and yellow perch.

What Do Brown Trout Eat?

Brown Trout like to eat aquatic insects, smaller fish and invertebrates. The young browns feed on zooplankton , aquatic insects like midges, black flies larvae, as well as small crayfish.  As they get bigger they feed on crayfish and smaller fish in their environment. They also readily consume other trout species including brook trout and rainbow trout.

Summary – What Do Trout Eat?

Successful trout will eat whatever food is easy and available. The large fish will often resort to larger prey in order get get the most food for the energy expended. During periods  of high water many fish will eat earthworms heavily. Many large trout will often even eat mice and other small mammals. The largest member of the trout family taimen have been known to eat prey as large as muskrats! Hopefully this article answers your questions about what do trout eat!