Chris Ellings, restoration biologist with the Nisqually Tribe, presenting on:
A study of Chinook distribution, feeding behavior, growth, and estuary residence to provide a baseline comparison for how the population may respond to large-scale ecosystem restoration.
Notes from Chris’s presentation:
Predicting a large response for restoring the Nisqually River estuary. So, what are the linkages between estuary restoration and more chinook smolts?
Wanted to look at broad distribution of chinook across the entire estuary and the nearby nearshore.
Studied otololith rings, which are earbones which give them an idea of where the fish are spending their time.
High abundance of chinook and chum in May and June. The entire estuary is a busy place in May through July.
Wanted to focus on natural origin fish, and how they use the estuary and where they stay. Reside there for an average of 16 days.
There are differences in natural origin chinook usage in two different sites. Less long term use in a restoration site that was shallower. In a deeper channel, there is longer usage by chinook.
They also looked at the diets of the fish using the site and compare that to what insects were available. Both wild and hatchery fish feed on the insects that were available at the time, wild fish with a broader diversity.