Spawning Trout

In the autumn the brown trout spawn while the rainbows take their turn in the spring. The areas the trout spawn are readily identifiable and are know as "redds". The redds are generally saucer-shaped nests dug by the female or hen in the clean gravel lining the bottom of streams. The redd is created by the hen while lying on its side and rapidly beating its tail up-and-down to create a current which allows the current to move the gravel slightly downstream. Up to two males then move alongside the female and the eggs and sperm are deposited simultaneously into the redd. The female then moves to the upstream edge of the redd, again beating its tail on the stream bottom to create a current releasing more gravel to bury the eggs. After this process is done, the eggs are abandoned.

In the case of the browns, the eggs incubate through the winter, hatch during late winter, and the tiny fry emerge from the gravel during the first warm days of spring. This whole process is, of course, temperature dependent. The number of eggs produced depends on fish size. An 8-inch mature brown trout may spawn 200 eggs, while a 10-pound female might spawn over 8,000 eggs. With this in mind, it is important to allow the process to take place undisturbed.

The browns will tend to spawn for a few months in some spots. It is bad form to fish to the spawning trout so keep an eye out for the redds and avoid them. The fish will tend to stack up down stream from the redds waiting to move in. If you see a fisherman near them who is unfamiliar with the sensitivity of the area, a kindly warning will not go astray.

Similarly with rainbows which spawn in the spring. The same considerations apply so watch out for the redds and steer clear to ensure that the trout have the best opportunity to spawn uninterrupted. There are enough natural predators and obstacles to the process without unnecessarily introducing more.

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