Rivrguy -
Yes the historical infomration is that our western Washington streams (especially the ones draining to Puget Sound and the Chehalis) were coho factories however we need to remember what that habitat look like two hundred years ago. The low elevation streams that are favored by the coho were heavily forested and the river flood plains where laced with aquatic habitats - multiple river channels, over flow channels, oxbow sloughs, wet lands and many beaver ponds. the result was excellent survival of the eggs placed in the gravel, 10,000s of acres of coho rearing habitat and vast networks ot complex habitats to capture and hold the carcasses of the spawning salmonids.

Since that time through deforestations, channel simplication, diking, wetland filling and draining, etc we have reduced both the capacity and productivity of the coho (and all salmonids) to a small fraction of what they once were. As a result we can end all harvest and sprinkle nutrient pellets to our hearts content and never see anything close to historical numbers returning to our rivers.

I think your biologist friend had only part of the equation. We have created these aquatic deserts through over harvest and habitat destruction. We can only regain what has been lost by addressing all those limiting factors. In fact through out the Puget Sound region harvest rates on wild steelhead, chinook and coho have been greately reduced over the last 15 years and many cases without much improvement in fish numbers. Those areas with the significant improvements in run sizes have been in those areas with the best habitat.

Any improvements in habitat restoration that can be made will magnify the benefits from any improvements in harvest, hatchery practices, or nutrient enhancement. To the point of this thread through habitat simplication in our river systems we have greatly reduced the river's ability to capture and hold the spawned out carcasses. On most of our river systems those carcasses are now flushed from the system by the regular fall/winter flooding prior to them breaking down and releasing their nutrients to the system. While that may a good program for Puget Sound crabs it does little for the young salmon.

Tight lines
Curt