On June 15, a commercial fisherman hired to remove invasive fish from the Illinois River system netted one of the largest bighead carp ever recorded, weighing in at 109 pounds. While the catch will not stand as an official record, since it was caught by net, it outweighs the IGFA all-tackle world record for the species by nearly 20 pounds.

Charlie Gilpin Jr., hired by the Illinois River Biological Station (IRBS) to net and remove invasive carp, caught the monster fish on the Illinois River near the town of Morris, one-hour southwest of Chicago. The IRBS posted a photo of the beast on Facebook, where they wrote, “This 109-pound carp won’t be causing any more problems for native fish and mussels!” 

Though Illinois and IGFA regulations state that fish caught with nets are not eligible for record status, the catch was a standout for the IRBS. “That is by far the largest bighead carp we’ve caught,” IRBS fisheries biologist Jason DeBoer told Shaw Local News.  “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.”

According to the Illinois Department of Natural Resources, Asian Carp arrived in the United States in 1963 as part of an experiment to reduce nuisance vegetation without the use of poisons that might enter the food chain. “Prior to the Clean Water Act, American rivers were often highly polluted and the bottom-feeding varieties of carp excelled in sewage treatment lagoons,” the agency writes on its website. “Arkansas breeders flushed the Carp into canals and waterways where they began to flourish and breed, gradually expanding into the Mississippi River and throughout the massive watershed of the river across 31 states.”

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The United States Geological Survey reports that they currently plague rivers in 18 U.S. states and have become a major ecological threat to midwestern river systems. The species wreaks havoc on native food chains and severely damages sport and commercial fisheries.

The IRBS is a monitoring and research facility funded by the U.S. Army Corps of Engineers and administered by the United States Geological Survey. According to the IRBS, Gilpin Jr. also netted a 90-pound bighead carp earlier in June.