Last spring, I got to go fishing for 6 weeks. It was FUN. Even in the relentless rain; even while carrying the boat up steep hills littered with blackberry brambles; even in the boot sucking muddy areas; even while rowing for almost 2 hours in a 12 ft boat so loaded with nets, traps, and gear that you hardly had room for your feet; and Yes, even in the reed canary grass so tall, your eyes would water, your nose would run, and you just hoped you found your way out.
The work took place in Deer Island slough and lower Tide Creek. Deer Island is located just north of St. Helens in Oregon. These slough areas just off of the Columbia River can be very important to migratory fish. A couple of local agencies are partnering with the private landowners to develop habitat restoration strategies that are both compatible with private land uses and provide benefits to anadromous fish and other species. Our office contributed to these efforts by providing information concerning fish presence, aquatic habitat conditions, and fish access to the various habitats. Existing tide gates at either end of the slough also left the question as to how well fish could pass through.
Jen, lead biologist for the project, was tasked with figuring this out. I was lucky enough to be her assistant for the project. So, one early day in March, we set off with enough nets, seines, traps, and water testing equipment to fill the back of large pickup. The area was new to both of us, so we did a bit of exploring to figure out our strategy.
The location, whether it was deep water, shallow water, vegetated water, lots of flow, little flow, determined our means of sampling. In short, we ended up setting minnow and crayfish traps, and hoop nets overnight in all of our reaches. We used a 12 ft boat to haul a seine five times per reach in the deeper water. At first a 5hp motor helped us to pull the seine, but a problem with the motor midway through the project forced one of us to row, while the other fed out the seine. This turned out to be Very hard work for the rower. In Tide Creek, we used a smaller stick seine as well as the traps and hoop net.
When we caught fish, which was all the time, we simply identified and counted them and weighed and measured all the salmon and trout. Just imagine counting thousands of threespine stickleback out of one net! Anyway, all the fish were then released unharmed, untagged, and unmarked. This is almost unheard of in the fish business.
What we found surprised us all! Of the 23 species of fish we caught, 12 species were native. Three of the non-native species were firsts for me: the amur goby, oriental weatherfish, and warmouth. Since we did find 5 species of migratory fish, we determined that fish could pass through the tide gates at least some times. This area seems very important to outmigrant Chinook salmon, since we caught lots of clipped hatchery fish. Also on the list of migratory fish were coho salmon, coastal cutthroat trout, Pacific lamprey, and steelhead trout. I’ll end by saying that this was surely six weeks of great fishing!
Click here for Assessment of Fishes, Habitats, and Fish Passage at Tide gates on Deer Island Slough and lower Tide Creek
Blog submitted by Donna Allard