By Corvo Rohwer, Puyallup Tribal News
Pulling a small boat along a rope by hand to a barge anchored in the White River, Puyallup Tribal Biologists Andrew Berger and Corey Corrick are out on the water not for recreation, but for science.
From January to August, the Puyallup Tribe Fisheries team is out on both the Puyallup River and White River daily, where they monitor juvenile fish populations and log data about river conditions. Berger described this hands-on work to be important, as it provides a way for the Tribe to stay updated and forecast fish populations within the local waters.
“We know how many hatchery fish are leaving because they count them when they leave the hatchery,” Berger said. “It’s the wild fish we don’t really have a handle on so explicitly.”
The science team’s day starts before they arrive at the water, gearing up at the Fisheries office and checking weather conditions and river flow before loading up. Berger said on a typical morning there are two teams of two, with one heading out to the Puyallup River and the other venturing to the White River. Once on site, the team members board a skiff and pull themselves along a cord to reach the screw trap barge.
“It’s kind of a funny boat ride,” Berger joked. “Which is good. I’m glad we don’t have to deal with motors.”
The screw trap is essentially a large cylinder that spins using the current of the river and captures a portion of migrating juvenile fish in a submerged box. This box can then be hoisted up to allow the biologists to count and sample the fish collected by the screw trap. Once a fish is collected from the box, it is transferred to a bin where it receives a light dose of anesthetic to ensure it can be handled and examined safely.
“Once you have the fish knocked out, you’re looking to identify species, get a fork length, note if it’s hatchery or if it’s wild, and then pretty much let it go,” Berger said. “Sometimes we’ll do extra stuff, like clip them for genetics.”
While Corrick carefully measured and examined the small fish, Berger assisted by logging the information. Monitoring steps can also include tagging the juveniles with PIT (passive integrated transponders) tags, similar to the toll passes you might apply to your vehicle, except instead of tracking when a car crosses a bridge, these monitor fish movements throughout a river.
“They’re like RFID tags,” Berger said. “If a fish comes by an antenna, beep, it gets detected. It’s pretty fun.”
The team also gathers information on the river itself, measuring turbidity and gathering environmental parameters from the United States Geological Survey to include in their data. Once the information has been logged, the juveniles are released back into the water and the screw trap box is lowered back down into the river. This process is done at least twice a day, once in the morning and again during the evening.
For Berger, the task of being on the water and monitoring fish is not only fun, but is personally rewarding.
“Fish are important for Tribal communities, this is a way of life for people here,” Berger said. “It’s a really cool thing that I can do this and help out the community.”
This work helps fish populations stay stable and safe throughout the years, and ensures the tradition of fishing remains intact. If you’re interested in learning more about the research, monitoring and evaluation that Puyallup Tribal Fisheries publishes, visit the Fisheries page on the Tribe’s website where you can find annual reports alongside additional information regarding the monitoring of both adult and juvenile fish populations.
