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About Siletz news / (Siletz, OR) 199?-current | View Entire Issue (Nov. 1, 2000)
TRIBAL PROGRAM NEWS The Estuary, The Hatchery, and More by Stan van de Wetering Estuary Project We spent most of September collecting depth, salinity, and temperature data for Siletz Bay. Using a Global Positioning System computer, we measured elevations at several hundred locations in the bay. These data will be used to produce a map describing water depths at high and low tides across the bay and throughout the marshes. Our main use for these data is to help us decide where to look for juvenile salmon in the spring when we are monitoring for habitat use. We also hope to use the elevation data to look at the effects of sediment transport on the shape and depth of the bay. Lamprey Project During August, I spent a week on Tenmile Creek collecting eel smolts. This fall we will look at the fat content of these little guys to prepare ourselves for a small experiment next summer. In past articles, we have covered our interest in increases in stream temperatures and previously described an experiment where we examined the maximum water temperature baby eels could tolerate before dying. It was surprisingly high (80 degrees). Smolting eels live off of stored fats for seven months prior to entering the ocean. Most animals are known to respond to increases in temperature with an increased metabolic rate, which means more energy is burned. For eel smolts, this means stored fats are burned as stream temperatures increase. At least that is the theory behind the question we will be asking. We will measure the total fat content of the eels sampled in the summer of 2000. From these data, we will determine mean fat content and the range of fat values, which will tell us how many fish total we will need next year. Next year, we will put three groups of eels in each of three unique high- temperature tanks for 60 days, then measure the differences in mean fat content between the three groups. We will then compare our current stream temperatures with those used during the experiment and suggest whether a potential negative effect 6 Frank Simmons and Miles van de Wetering survey the area around the new hatchery pond. is present or not. That is, are current high stream temperatures affecting eel smolt survival during the summer. Hatchery Project As described in our last update, we had plans for three projects on the hatchery property this summer/fall. The first, digging a new earthen pond where the old raceways were buried, is now complete. Quinn Murk of Total Tree Logging was our contractor for this work. Quinn spent a week removing the old concrete structures, pipes, wires, and various other types of garbage from the site. It was quite a mess and we spent much more time cleaning out refuse than digging the actual new pond. We ended up storing a fair amount of concrete on the corner at the quarry site. We hope to find a grant this year to move the refuse off the hatchery property. Quinn did a great job and put in several hours of volunteer time. The second project was the adult fish trap. We contracted the work with Marv Willey and he too did a great job. We have not set a date for building the pole barn, which will provide shelter for many uses, but we expect it to be done by Christmas. We will use our 3K charitable fund grant to finish the water, sewer, and electric setup Mike Elkins helps paint at the hatchery. this month, which will allow a camp host to move in. As most of you know, the hatchery site is not always the best choice for harvesting bright fish unless the rains hit at just the right time. I’m told that in the past 10 years or more, this site has not produced much of anything. This looks like an improvement on the recent past and if we get lucky and see a 1 percent survival rate for adult coho, we should have between 350 and 450 coho adults returning to the Rock Creek system. (See Hatchery on page 7)
