Return to the Trout Stream

Two years ago, I wrote about brook trout in a Caledon stream. I returned to the limpid waters of this stream this fall to commune, once again, with these awe-inspiring fish.

Beautiful fish born of beautiful habitat, these trout are nurtured by cool, crystalline water. Sully that water with silt, warm it with stormwater run-off or poison it with effluent, and the trout disappear.

In the videos below, most of the trout are brilliantly coloured males. But the largest fish in the gathering is a female, a little less colourful, who, from time to time, turns on her side and shudders – shaking her powerful tail to clear sediment from the stones on the bottom of the stream. She’s cleaning house prior to releasing her eggs.

With the streambed cleared of debris, her eggs will slip into cracks between the stones where they will be protected from predation and from being swept away. Males release their milt (sperm) to fertilize them.

The cool riffling water moving through the stones will provide the vital oxygen the eggs need, but there is another habitat component that further highlights the connection between brook trout and clean water.

The brook trout redds (nests) are usually located in areas of upwelling spring water. Filtered and clean, this water bubbles through the streambed stones, enveloping the eggs in a womb-like environment that is warmer than the river water. This ensures optimum conditions for the development of the eggs over winter.

If we tamper with the surface or groundwater needed by brook trout to maintain their health and reproduce, we will lose them. Gone will be these glorious manifestations of pristine nature. Let’s not allow that to happen.