November 26, 2005

Mystery Coho Kill in Byrne Creek

I got a call from two volunteers with the Byrne Creek Streameepers today who were out patrolling the creek for returning salmon spawners. They had come across nine dead coho salmon, all female, all un-spawned, and all looking like they were fresh out of the ocean.

This was unusual for several reasons. First, we rarely see that many dead spawners in one day in our small, urban creek. Second, the fish were in pristine condition, without the usual bodily and color changes that salmon exhibit when they return from salt water to fresh water to spawn. Third, they also found a couple of dead coho smolts -- young fish that live in the creek for a year after they hatch before going out into the ocean.

Coho are our "canaries in coal mines," for they seem to be more sensitive to pollutants than other fish.

We got the word out to a City of Burnaby environmental officer, who went down and took some water samples, and some of the dead fish. We hope an explanation will be found, but often in such cases nothing can be pinpointed.

The kill distressed me, for it added to the toll of female coho that have died before spawning in the creek this autumn.

Posted by Paul at November 26, 2005 06:13 PM