During the past seven seasons chinook size and numbers have both decreased but the idea that these changes can be reversed by fisheries managers hasn't changed. It is time to realize that the tweaks to harvest management or even stopping harvest will have little effect. Human actions are a major contributor to the changes, climate change, ocean acidification, pollutants, and industrial fisheries that may have small direct impacts on an individual species but a great impact on the marine ecosystem they rely on.

An example is size at maturity, computer models demonstrate that harvest might reduce size at maturity, but there is growing direct evidence that pollution has the same effect. At the recent Salish Sea Conference information was presented that size and age of maturing Puget Sound chinook is reduced by exposure to persistent organic pollutants. There are many lab studies that demonstrate that the offspring of maturing females (not just fish) exposed to endocrine disrupting chemicals can have lower growth and survival. Even more important is that the changes are epigenetic, the fish that survive pass the new traits to their offspring. These kinds of pollutants are everywhere, in both the marine and terrestrial environment. Salmon are a fast evolving species, 10 generations can lead to a lasting change. Smaller, younger fish would have less exposure time to pollutants in the marine environment, speculation but it could be the future.

Disease (Parker's post of 2006), ocean temperature changes,and freshwater habitat are all contributing factors. Along with pollution and harvest no one thing can be assigned the blame for decreasing size and numbers. More likely it is a synergistic effect brought on by a combination of these stressors.

There is going to be a two day workshop, open to the public, in Anchorage in early December that will examine some of the problems and potential solutions to the Yukon Chinook problem. It is sponsored by AYKSSI, more information, speakers and topics, can be found at the link below.

Salmon Outreach Workshop