You might not notice them. Small, minnow-size fish that dart into reeds near the river banks with a passing shadow. Timid they may be. But stickleback have quite a story to tell biologists in Central Oregon — and around the globe.
On a warm, sunny summer morning on Oregon’s high desert, dozens of stickleback in the Crooked River have made their way into a fish trap set by biology major Deidre Hall. A few yards away, wearing shorts, t-shirt and river shoes, Deidre scans the makeshift, mobile lab she has set up on the tailgate and in the cab of her pick-up truck.
She checks off her equipment — test tubes, pipettes, aluminum foil, Sharpie pens. Satisfied, she grabs a bucket, pliers and net, and steps hip-deep into the fast running river with biology instructor and researcher Ann Petersen.
“Aaagh — it’s freezing!” they shout nearly simultaneously, and laugh.
Deidre is one of eight undergraduate students at Oregon State University’s campus in Bend working on The Stickleback Project, a research study led by Ann. The team’s mission is to learn what stickleback can tell them about a specific kind of pollution emerging in area rivers. The pollution type is an environmental endocrine disruptors, a contaminant that can cause serious changes to organs, among other things.
The results of the students’ stickleback studies will help paint a picture of how Central Oregon’s rivers — and the contaminants in them — affect the biological health of their inhabitants and other living beings, including humans.
Rapid growth in Central Oregon has changed land use in the region. New development, road and agricultural activity has brought and continues to bring pollutants — herbicides, pesticides, pharmaceuticals and plastics — into the watershed.
Understanding how these pollutants affect wildlife health and threaten human health is important work and a multi-layered challenge. Stickleback can help.
The small fish are powerful indicators of evolutionary change. Found in northern temperate climates in Europe, North America, Japan and elsewhere, and in both salt and freshwater, stickleback respond to their environment much like canaries in a coal mine, alerting biologists to changes in water conditions.
Seven populations of stickleback along the Deschutes and Crooked rivers — some near human development and others more remote — have become the focus of the student research team.
Deidre’s more than passing interest in fly fishing prompted her site selection. Her charge is to learn if stickleback at a few angler-favored locations show signs of disease from pollution, particularly in their reproductive organs.
If they did, it could also suggest that a flyfisher favorite, the iconic redband trout, may be at risk. It’s a bonus to The Stickleback Project and to flyfishing advocates. And it’s a small example of how stickleback speak for other species.
Deidre has joined a community of hundreds of researchers in the northern hemisphere with a deep fascination — almost affection — for stickleback. Jokes and puns abound within the research community. Looking into the bucket of swimming stickleback that Deidre has just pulled from the river, an observer asks how the researchers tell sex so easily.
“Oh, you’ll get your stickle sense,” Ann responds. Deidre smiles wryly.
Their humor hints at the respect researchers have for stickleback, and for one another. To help advance studies globally, researchers in England contributed supplies for Deidre’s work.
Here in Central Oregon, Ann and her team are pioneers. They are the first to investigate the impact of pollution on stickleback in Central Oregon’s rivers.
Back at the tailgate with the bucket of 80 or so stickleback, Deidre shows Ann her new system for labeling test tubes, which better identifies site location, date and individual fish.
“Deidre’s system is smart,” said Ann, explaining, “I bring what I learned — my students improve it.”
Deidre puts a few drops of aquatic anesthetic in the bucket to slow the fish's movement and allow her to work with them.
She slides on latex gloves and with minimal guidance from Ann — a tip here and there — she gets to work. She’s after a blood protein called vitellogenin, normally found in the blood of females.
When male fish have high levels of vitellogenin in their blood, it is a telltale sign that they have been exposed to an endocrine disruptor.
Deidre nets an anesthetized female and places it on a cutting board in the center of her lab bench, the tailgate. With a blade, she slices a small opening at the tail. Holding the fish lightly between the fingers of one hand and at eye level, she massages with a motion that pushes blood toward the tail. In her other hand a tiny, slim, glass pipette is ready to draw blood.
Ann and Deidre’s heads are nearly touching as they both peer into the tiny stickleback’s body. It takes Deidre a few breathless milliseconds to find the right angle to collect blood and only blood, and no other fluids or tissue.
“Elbow down, keep your elbow down to steady your hand … there you go,” Ann coaches and encourages, as Deidre delicately maneuvers the pipette around the fish tail.
Working fast is key. It takes seconds for blood to clot, and if it does, she has to start over with a new fish.
“There we go,” Deidre whispers with both relief and confidence, as blood moves up the pipette.
She transfers the blood — a drop the size of pinhead — to a test tube and carries it swiftly to the truck’s cabin. That’s where a mobile centrifuge sits atop the console between the driver and passenger seats, plugged into the nearby cigarette lighter. The centrifuge whirls, separating the blood, leaving the clear vitellogenin fluid at the bottom of the tube. It’s not much to look at, but for researchers like Ann and Deidre, it’s gold.
By now the day is heating up. Deidre is sweating from the intensity of the work, and the movement between the bucket, the tailgate and the cabin of the truck. She wipes her forehead with her forearm, avoiding contaminating her gloves.
She has been working on the Crooked River for most of the summer and has her work down to a system, but the intensity still surprises her. She takes a break, saying, “I never knew how busy it would be in the field.”
Deidre knew her path was science even at an early age. Raised on a family farm in Scio, a small, agricultural community on the west side of Oregon’s Cascade mountains, she spent a good deal of time caring for animals. Her interest in biology propelled her through school; she’s the first in her family to go to college.
It hasn't been an easy road. Her academic career was put on hold for a year when she and her husband became temporary guardians of her nieces and nephews, immediately expanding her family of one son.
“It’s family. It’s what you have to do,” she shrugged as she watched the centrifuge.
“Deidre bucks every trend,” said Ann. “It might have been easier to stop after high school, or gone to work instead of college, yet here she is focused on a Ph.D.”
“I want to work with salmon for my doctorate,” she says, although she and Ann both know that with six more undergraduate classes to go and a relentless curiosity, she may well change her mind.
By the fall, when she wraps up her research, she’ll have a lot to be proud of and good experience to include in her graduate school applications.
She can add fundraising, too. For her research she received a grant for $5,000 from Central Oregon Flyfishers, adding to the $3,000 she successfully sought from the Layman Foundation and the Student Fee Committee. The money pays for gas she uses traveling between campus and her research sites, and for lab supplies and equipment — including the portable centrifuge in her truck.
A few days later, Deidre is in the biology lab. She and her fellow undergrad stickleback researcher Tony Brande are talking about the state of their summer efforts. There are only a few more weeks before the weather, and studies, will force them inside.
The two are headed to an academic conference on environmental toxicology and chemistry in the fall. Typically the grounds of grad students, post docs and university researchers, academic conferences don’t often accept undergraduate researcher submissions. It’s quite an accomplishment for them both.
“Ann’s a good mentor,” Deidre says, modestly explaining the achievement.
It’s easy to see that Deidre and her research team partner would rather focus on stickleback. Nearby a deep freezer contain stickleback specimens and others have been sent to away to be processed. They’ll come back on slides, cross sections of organs easily visible for analysis.
By winter, Deidre will have wrapped up her stickleback work, and packaged it ready for Ann to assign it to a new undergraduate team member in the spring.
“I’ll miss this,” Deidre says, thinking about her future and surveying the lab her. “But I’ll check in, I’ll always check in.”