Wildlife agencies and fishermen in Illinois are using a Chinese technique to catch Asian carp, an invasive fish species threatening the Great Lakes ecosystem.
Part of what makes the Asian carp so formidable is the species’ ravenous appetite. In one day, an Asian carp can eat 20 percent of its body weight, which can reach a whopping 100 pounds. The fish deplete waters of necessary food, like plankton, for other aquatic life.
The fish were imported into southern U.S. states in the 1970s to clean the waters of aquatic farms, but flooding is believed to have eventually sent them into the Mississippi River.
The Chinese method uses a vertical net, called a seine, that’s weighted down to catch fish that have been corralled into a large, shallow body of water. The weights are eventually raised to trap the fish in the net, which is drawn tighter to haul the catch in.
Related: Budget Cuts Could Hinder Efforts to Keep Asian Carp Out of Great Lakes
Unlike some other fish species, Asian carp can be “herded” or directed via loud sounds. For this reason, scientists and fishermen drive the fish in the direction of the net by using loud underwater speakers or banging objects against boats.
After two weeks of corralling Asian carp, the Illinois Department of Natural Resources recorded a load of about 7,000 pounds of Asian carp on March 9.
While the fish is considered a delicacy in China, it is primarily used in the U.S. in products like organic fertilizer and dog food.
Equipped with electric barriers to keep the invasive species out, the Chicago Sanitary and Ship Canal is considered the last corridor for this foreign fish to reach the treasured freshwater of Lake Michigan and the rest of the Great Lakes.
Asian carp haven’t yet been found in the canal, but their travels upstream in the Illinois River is still a concern to those monitoring the Great Lakes ecosystem.
Fishermen and wildlife biologists constrict the seine net to reveal their catch of mostly Asian carp. (Evan Garcia / Chicago Tonight)
From 2010 to 2015, the Illinois Department of Natural Resources removed four million pounds of Asian carp from the Illinois River, according to the state wildlife agency. (Evan Garcia / Chicago Tonight)
The Brandon Road Lock and Dam, located about 25 miles upstream from where the IDNR caught Asian carp, is the site of a study by the U.S. Army Corps of Engineers to keep the Asian carp out of the Great Lakes. (Evan Garcia / Chicago Tonight)
Democratic Senator Debbie Stabenow of Michigan said the Trump administration has delayed the scheduled release of preliminary findings from the Brandon Road Lock and Dam study. (Evan Garcia / Chicago Tonight)
A net sets the parameter for where the Asian carp will be captured. (Evan Garcia / Chicago Tonight)
Gill nets tangle Asian carp and native fish alike. (Evan Garcia / Chicago Tonight)
A fisherman throws a bigmouth buffalo, a native fish, back into the water. (Evan Garcia / Chicago Tonight)
Scientists use speakers to blast loud sounds underwater, directing the Asian carp. (Evan Garcia / Chicago Tonight)
A fisherman begins pulling in a seine net. (Evan Garcia / Chicago Tonight)
The seine net is pulled closer. (Evan Garcia / Chicago Tonight)
The seine nest is lifted to keep any fish from escaping. (Evan Garcia / Chicago Tonight)
As the seine net is pulled tighter, the Asian carp – a fish species known to leap out of the water – make a jump towards freedom. (Evan Garcia / Chicago Tonight)
Fishermen and scientists sift through the catch to sort Asian carp from native fish. (Evan Garcia / Chicago Tonight)
Native fish are thrown beyond the seine net. (Evan Garcia / Chicago Tonight)
Asian carp are loaded into a boat to eventually become fertilizer, dog food or other products. (Evan Garcia / Chicago Tonight)
Follow Evan Garcia on Twitter: @EvanRGarcia
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