Mt. Nusatsum

Mt. Nusatsum

Thursday, March 22, 2012

Fry

March and April are normally the peak months for the downstream migration of salmon Fry in the Bella Coola River (fry are small fish that are newly emerged from the river bed gravel).  These are mostly pink and chum salmon fry that would have been eggs deposited in August through October last fall.  How fast they hatch and develop through the various stages to emergent fry is totally dependent on water temperature. 

In most 'normal' years, ie years in which the Bella Coola River and its tributaries are not flooded in the fall, they were would be fairly healthy and easily visible to the eye numbers of fry along the stream margins.  Their main migration downstream to the ocean happens at night to make it tough for predators - and there is a lot of those namely cutthroat trout, Dolly Varden trout, sculpins, Kingfishers and River Otters.

I've been watching this year though and the numbers by simple visually observation don't seem really abundant - which is an observation consistent with a relatively low return of salmon in 2011 and another very damaging flood in September 2011 (third year in a row).

The box in this photo - an inclined plane trap - operated by the Department of Fisheries and Oceans to live trap, count and release fry is the best indicator of abundance. Hopefully they are catching a few this year.  Grizzly

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