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EIU 360

EIU 360

Catfish Tracking

Research of Biological Sciences grad student has her in tune with the local flathead catfish population

Sarah Huck is on the Wabash River in Hutsonville, Ill., tracking catfish after catfish, but she doesn’t want to make her research impersonal. She names the catfish after people in her lab and remarks about which ones are her favorites as she tags them.

“I guess I do get slightly attached to specific fish that I've been tracking for a long time," she said. "I'm always curious where they will be next month.”

Huck, a master's student in the Department of Biological Sciences and part of its fisheries and aquatic research lab, travels 175 miles total down the Wabash River in a boat driven by Les Frankland, an Eastern alumnus working for the Illinois Department of Natural Resources. For Huck’s research, she is working on a tracking project to determine population patterns of catfish.

She tags flathead catfish only, typically finding them in dense logjam habitats. Huck surgically implants an ultrasonic transmitter to each fish, securing this to the pectoral girdle.

“It makes me feel like a surgeon for a little bit,” Huck said.

In a separate procedure, each fish is tagged with a Floy tag, essentially a piece of plastic secured to the fish's dorsal fin and marked with an individual identification number for the fish and contact information for the researchers. Since the scar from this procedure becomes almost invisible, the Floy tag will let fishermen know a fish is being researched.

"This doesn't mean fishermen cannot harvest the fish," explained Huck. "I always tell them that they can harvest the fish, just give me the ID number on the Floy tag and mail me the ultrasonic transmitter -- it's reusable."

By tracking the fish, Huck is able to get a complete look into almost every aspect of a catfish’s life. The data she collects gives her a good look at the movement patterns and habitat use of flathead catfish during all four season.

“It’s kind of a life history behavioral question there,” she said.

Tracking the fish can also ensure they are healthy and in their expected quantities. Because the catfish are one of the top predators of fish, if anything were to happen to them, the entire system would be thrown off.

“Knowing specific habitats the fish use throughout the year is very beneficial to know," she said. "If habitats within the system become degraded and the population becomes negatively affected, the information from my research will be helpful to identify and provide these crucial habitats needed for the survival and persistence of the species.”

If there were problems, though, the type of research Huck does would show what changes of regulations should be made. So far, the results show the population is healthy and thriving despite the fact that flathead catfish are one of the most targeted species in the system.

“The fish are nice and plump, and they don't show any indication of an over-exploited population,” she said.

Before releasing the fish back into the water, Huck places them in a recovery tank for five to 10 minutes.

Some fish are harder to be tracked than others, Huck said, depending on if they are in a place that can be easily pick up the ultrasonic signals.

It’s not just Hucks’ own tagged fish that she finds, though.

She’s detected Asian carp that other schools, like Purdue University and Southern Illinois University - Carbondale, released into the water near St. Louis that have swam back and forth. These fish then swam up the Mississippi River, across the Ohio River and up to the Wabash River where she found them, she said.

If Huck ever finds tags from other schools doing research, she sends out an email to inform them of her discovery.

As mentioned, Huck's  fish are also found by others, usually by recreational fisherman. If fishermen happen to catch one of the 44 fish part of Hucks’ tagged group, they can call the phone number attached, and Huck can then identify the fish specifically.

Huck still encourages these fishermen to harvest what they catch -- "It's their river, I just do research in it," she explained -- she just wants to know which fish are being taken out of the river.

"I ask a variety of questions pertaining to mode of capture, size and health of fish, et cetera," said Huck. "Then they mail me the ultrasonic transmitter, and I mail them a report about that particular fish: Where it has been since I began my research, how big it was when I tagged it, et cetera."