In an effort to minimize the number of Asian carp in area waters, researchers are hoping the fish have a sweet tooth.
Faculty from Joliet Junior College, members of the Illinois Department of Natural Resources and commercial fishermen boated across the Illinois River from Starved Rock Marina on Friday to retrieve nets that included blocks made of candy.
Patrick Mills, chairman of the Natural Sciences department at Joliet Junior College, said the sweet treats could be used to attract the fish to larger nets.
“Asian carp are kind of like public enemy No. 1 in terms of invasive species because they essentially eat the plankton in the water, which the small fish eat,” Mills said. “So you’re basically killing the food chain of this base. That’s why these fish are so bad for our ecosystem, as they’re basically killing the fish in their crib.”
Mills said if the department can find the right flavor to attract the fish, it could assist in controlling their population numbers and re-establishing a natural ecosystem. Additionally, Mills has done research on amino acids that could double the success of the candy blocks.
The researchers took boats out to retrieve nets that had been placed in the river along with blocks of pineapple-flavored candy. The candy was placed in a bag with holes in it so the product would seep into the river.
Greg Taylor of Taylors Candy made the product specifically for this project, and he rode with the team to see the result. Taylor said his company also made blocks of garlic, which will be used in the future, as well as aniseed, or black licorice flavor, which was tested earlier.
He worked with researchers to determine which flavors would be enticing to the fish.
“You can’t ask the carp, so through their research, knowledge of fishing and basically just through working with them, we figured it out,” Taylor said.
Mills said the candy-based bait also is less destructive to the other species that call the river home.
“There are many, many ways to get Asian carp out of the river, and we want to avoid poison. We want to have a nondestructive technique, because the last thing I want to see is poisoning the river,” Mills said. “There’s always the casualties of war, and we don’t want the other fish to suffer.”
The first catch of the day resulted in success, as a large number of Asian carp was caught in one of the candy-filled hoop nets. The researchers pulled the carp from the water and tossed back some catfish.
Clint Garwood of Joliet Junior College said the researchers hope to find a flavor that attracts the invasive species and doesn’t affect the natural ones. Although there are some universal flavors, such as aniseed and garlic, others attract more specific species.
The candy blocks are large when held in a person’s hand, yet small when compared to the rushing Illinois River, but Garwood said that’s not a problem, as flavor typically is oil-based and mixes into the current.
“The fish smell but do so in a water environment, so oils tend to come up. So they’ll smell something, and that triggers them to forage,” Garwood said. “They’re super sensitive to what triggers them to find food. It’s like how a shark can smell blood a mile away. For these fish, they’re picking up a light scent even in a current like this.”
Pineapple doesn’t have a natural oil, so a synthetic flavor was created for the test.
Garwood said the team had a good pull of fish throughout the day, but numbers were low compared with previous years.
IDNR Asian carp project leader Matt O’Hara confirmed this with local fishermen and said carp have not yet been as prevalent in the main channel for spawning.
He said water temperature and current flow get them to the main channel, and their usual presence might be delayed because of the extended time it has taken for spring weather to hit the area.
Garwood said the fishermen in the area already know where the fish tend to reside, but the candy is an effort to speed up the process of catching the carp and removing them from the river.
O’Hara said from there it’s up to the market to develop and create a demand for the fish on the mainland, such as China.