A commercial fisherman working on the Illinois River near Morris netted one of the largest bighead carp ever recorded on June 14. The giant carp weighed 109 pounds, according to the Illinois River Biological Station. That’s roughly 17 pounds heavier than the standing Illinois bowfishing record, and nearly 20 pounds bigger than the IGFA all-tackle world record for the species.
Illinois and IGFA regulations dictate that fish caught with nets are not eligible for record status, but the IRBS celebrated the catch anyways. Bighead carp are an invasive species in the Midwest, and the Champaign-based research facility has long been working to reduce their numbers in the Illinois and Mississippi Rivers. Commercial fisherman Charlie Gilpin Jr. was working on one of these removal crews when he hauled in the 109-pound bighead.
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“This 109 [pound] carp won’t be causing any more problems for native fish and mussels!” the organization wrote in a Facebook post on June 16.
Responding to a comment on its post, the IRBS explained that bighead carp are one of several Asian carp species that were introduced to U.S. waters during the 1970s to control aquatic vegetation and limit algae growth. Some of these fish escaped into the Mississippi, where they’ve expanded to the point of overwhelming native fish populations and even posing a safety hazard for boaters.
“[These] high-profile invaders, the Asian carps (i.e., silver carp, bighead carp, black carp, and grass carp) have had a profound effect on Illinois and the Mississippi River Basin’s economic and ecological resources,” the organization writes on its website.
Bighead carp are now present in at least 18 states and the species is firmly established in both Illinois and Missouri, according to the USGS. But in all the years that fisheries managers have been monitoring their populations, few have ever seen a bighead carp as large as the one Gilpin netted this month.
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“That is by far the largest bighead carp we’ve caught,” IRBS fisheries biologist Jason DeBoer told reporters. (DeBoer was on board that day monitoring the crew and photographed Gilpin with the fish.) He explained that the massive female carp was turned into liquid fertilizer, which ensures that it won’t ever spawn in the Illinois River again.
“From the fish’s point of view, the larger you can be for a female like that, the more eggs you can grow every year and the greater your chances of successfully passing on your genes,” DeBoer said. “The reason a fish that big is a problem for us is that it’s an invasive carp that makes a million or 2 million babies every year.”
