Aggies Help State with Fall Salmon Count
Thursday, Sep. 25, 2008
Aggie undergrads made an official count of bright red kokanee salmon in a stretch of the Little Bear River for the state of Utah. The fish are currently at the peak of their autumn spawning run.
From left, Watershed Sciences faculty member Phaedra Budy and students Joe Crawford and Chiyoon Song discuss fish tallies.
Along with flame-hued leaves illuminating northern Utah’s mountains and valleys with a blast of fall color are scores of red kokanee salmon making the last leg of their life’s journey through local streams and rivers.
“You don’t usually think of salmon when you think of Utah,” said Joe Crawford, an undergraduate fisheries and aquatic science major at Utah State University, who counted hundreds of the fish within minutes in a small stretch of the Little Bear River.
With nine classmates, Crawford joined Ben Nadolski, aquatic biologist with the Utah Division of Wildlife Resources, Sept. 23 to conduct an official kokanee count along the river’s east fork near Cache County’s Porcupine Reservoir. The undergrads are students in faculty researcher Phaedra Budy’s Fish Diversity and Conservation class.
“The data we collect today will determine how we manage the fish tomorrow,” said Nadolski, a USU alum who tracks population dynamics of various fish species and manages the reservoir’s fishery.
Displaying graphs of fish counts from the past 25 years, Nadolski invited the students to surmise why significant fluctuations in population have occurred in the past decade. The undergrads cited whirling disease that claimed large amounts of young fish in the 1990s and drought that contributed to lowered water levels.
“Recent dam repairs and increased popularity of recreational fishing are also stressors,” Nadolski said. “We’ve also had changes in fishing regulations, which impact fish populations.”
In teams of two, the students, dressed in waders and armed with mechanical counters and GPS units, tallied several thousand kokanee, now at the peak of their autumn spawning run.
Gathering at the end of their treks to compile collected data, students compared sightings of male fish sparring for mates and battling against the current. Many noted the bedraggled condition and whitened tails of the fish.
“The white scales indicate fungus,” Budy said. “The fish are literally rotting away as they fight their way upstream. Every ounce of energy they have is being expended on this final journey.”
The kokanee, close relatives of sockeye salmon, are semelparous organisms, she said, meaning each individual reproduces only once in its lifetime then dies shortly thereafter.
The trip to count kokanee is among a number of field activities Budy is conducting with her students during the semester. The class has also visited Fossil Butte National Monument and Bear Lake and will conduct trout sampling on the Logan River next week.
“This is a hands-on class to introduce students to fisheries management,” Budy said. “We acquaint students with varied types of aquatic research and offer opportunities to work alongside professionals in the field.”