Salmon Run

One of the many perks to living in Victoria is being able to witness a very interesting natural phenomenon as salmon return to Goldstream Provincial Park, only 16km away from the provincial capital. After the fuel spill earlier in the year, there was uncertainty if the salmon would return but luckily some did.

It seems as though I was a bit late in witnessing the salmon run in all its exciting glory this year but it was still very interesting to watch nature - perseverance, sex, and death - in its rawest form just a few feet away.

Borrowing the words of one of the Park's interpretative signs:

From October to December, Goldstream Provincial Park is host to one of nature's most fascinating spectacles. It begins when three species of Pacific salmon, compelled by an irresistible urge to forsake the rich feeding grounds of the Pacific coast, return to this stream to spawn a new generation.

Upon reaching the spawning grounds, male chum develop large hooked jaws with dog-like teeth, and purplish bars along their sides. Females develop a dark stripe. The female selects a patch of gravel and is joined by males who fight continuously to be near her. Males moves back and forth, occasionally quivering over her back.

The female digs a redd (a series of nests) in the gravel by turning on her side and thrashing her tail along the stream bottom, causing rocks to be lifted and carried downstream by the current. Testing the depth with her anal fin, she continues to dig until the nest has reach the right depth - as deep as half a metre.

The female releases about 400 eggs into the nest to be fertilized simultaneously by milt from the male. Time is critical because once the eggs swell and harden, they can no longer be fertilized. The female then moves upstream to dig a new nest. This excavation covers the deposited eggs just downstream. The process continues until about 3,000 eggs have been laid.

Males may leave the redd site to look for another egg-bearing female but the female remains to prevent others from claiming the territory and digging up her eggs. Weakened and battered, both males and females are dead within 10 days of entering the stream. 

A new generation of salmon now lies under the gravel, awaiting its own battle for survival.

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