Mussel Mania - Part 1

I never really thought about freshwater mussels until a few years back. Now I think about them all the time. Especially since I will soon be conducting a small pilot project studying them in Merrill Creek. More on that later. They are fascinating creatures. Even though they are one of the most endangered groups of animals on Earth, very little is known about the life history and habitat needs of many species.
We do know that freshwater mussels are dependent upon fish. After mussel larvae, called glochidia, are released from the female into the water, they have a very short time to find a host fish. If they find one, they will clamp onto its fins or gills, form a cyst around itself, and remain there for days or even months. During this time, the fish may swim many miles, thus helping to disperse mussel populations. Anyway, the chances of glochidia finding a suitable host, (yes, some mussel species are dependent upon only certain species of fish), landing in a suitable habitat after detaching, and reaching adulthood can be as high as 1 in 100,000,000. All I can say is WOW. Stay tuned for more interesting facts about freshwater mussels. If this has piqued your interest, go to the Pacific Northwest Native Freshwater Mussel Workgroup. There you can read a few documents or download the 2nd edition of the Field Guide to the Freshwater Mussels of the Pacific Northwest. And if you are ever wandering around in a creek and find any mussels, I’ll bet they would love to know.

Women in Science

On Feburary 3rd, I had the opportunity to be a guest speaker at the "Women in Science, Engineering, Mathematics and Technology (STEM)" event at Clark College in Vancouver, WA. The women in STEM seminar is an open forum designed to welcome women into the science community and broaden their perception of careers in math and science. It's also a great chance for college students to network with other female students, faculty, and professionals.

I talked about my career as a Fish Biologist, what I do on a daily basis for my job, and the educational requirements necessary for a career in fisheries management.



It was a great way to spend an afternoon, and I hope to be part of this awesome program in the future!

Maureen

Going Fishing!

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