Do Trout Eat Frogs and Tadpoles?

Few anglers seem to have witnessed trout feeding on trout or tadpoles, yet they seem like such an easy meal. Tadpoles, in particular, seem far too slow and calorie dense to be ignored by a large predatory trout. If you’re a bass or pike angler new to trout fishing, I’m sure you’ve asked yourself why is no one fishing with frog lures for trout?

Do Trout Eat Frogs?

Turns out that yes, yes they do.

In areas of South Africa stocked with Rainbow trout, it’s commonplace to see rainbows stuffed with smaller species of local frogs (and tadpoles). Perhaps these species of frogs are less adept at avoiding predation than their northern hemisphere cousins? In any case, it seems to be more prevalent in South Africa than in Europe or North America.

That’s not to say trout don’t feed on frogs up here in the northern hemisphere though. Brown trout in some frog dense water will actually stalk frogs along the margins, much like a pike would. Creeping up on them before striking and making a meal out of the unsuspecting amphibian. If you can find a situation like this, it makes for very exciting sight fishing.

Do Trout Eat Tadpoles?

Yes, they absolutely do. While trout feeding on frogs seems to be a mostly incidental occurrence, there are many bodies of water in which trout regularly feed on tadpoles.

Perhaps unsurprisingly, brown trout are especially eager to take tadpoles when the opportunity presents itself. Rainbow trout and brook trout will also eat tadpoles in the right situations.

Trout living in ponds or lakes are much more likely to eat tadpoles than river-dwelling trout. This has to do with the difference in the way trout feed in these different habitats.

The reason that trout in lakes and ponds are much more likely to feed on tadpoles, is partially because there tend to be more tadpoles in these environments than in rivers. It’s also due to a difference in how trout feed in still vs moving water.

River-dwelling trout sit in the current and generally wait for food to drift by them. Trout in lakes and ponds don’t have this luxury, and often have to prowl and cover water to find prey. This difference in feeding behavior makes trout in lakes and ponds more likely to cross paths with tadpoles.

Tadpoles like still, calm water and will avoid even mild current. This means they hug the margins very closely in rivers, and as a result, will rarely come into the feeding zone of trout.

Lakes and ponds are different. Tadpoles have the freedom to swim deeper and further from shore without getting swept away. Here, they are much more likely to cross paths of not just trout, but any predatory fish. Walleye, bass, and young pike will all make a meal out of tadpoles in this environment.

For a specific example of trout eating tadpoles, take the non-resident brook trout introduced into California. A number of the high Sierra lakes had brook trout introduced for angling opportunities many years ago.

It turns out that there were no tadpoles found in the lakes which had stocked brookies, and the frogs disappeared shortly after. In the 1990’s a biologist performed an experiment in which he removed the trout from several lakes in the region. Shortly after the tadpoles and frogs returned to the lake. Pretty solid evidence that the trout were feeding on the tadpoles and (possibly) the adult frogs as well. If you’re interested the scientific paper can be found here.

Final Thoughts

Insect, fish, and crustacean lures and flies are commonly used for trout. Frog and tadpole lures seem to be left to the bass and pike anglers though. Perhaps it’s time to try lures mimicking these amphibians on trout?

I have yet to catch a trout on a frog imitation, but I have caught both brook and rainbow trout on tadpole flies that I’ve tied. Whether the trout thought they were actually tadpoles or weird looking minnows I can’t say for sure, but they did work. These weren’t huge bullfrog tadpoles I was imitating with this fly. The fly instead mimicked the smaller inch long tadpoles you often see swimming in the margins.

Want to read about some other odd diets of fish? Check out these 6 fish that eat birds.