The search continues to find flying fish launching from our Mississippi River waters. The silver carp is notoriously known as the flying fish that leaps out of the water when disturbed by passing watercraft. Hundreds of fish may jump toward the sky in unison, hurdling 10 feet high and 20 feet horizontally, and many weigh between 10 to 15 pounds.
U.S. Fish and Wildlife Service biologists from the La Crosse, Wisconsin, Fisheries Office netted Mississippi River Pool 13 waters from Clinton to Sabula in fall of 2015 in search of these Asian aerial aquanauts. The good news is that no silver carp or its cousin, the bighead carp, were caught.
The bad news is that silvers and bigheads are migrating upriver in large numbers. Research is currently being focused in Pool 19 to document Asian carp migration, study their reproductive success, identify feeding behaviors, and determine what factors may limit their spread.
Western Illinois University’s Department of Biological Sciences, the U.S. Geological Survey’s Upper Midwest Environmental Science Center, Missouri Department of Conservation, and the USFWS La Crosse Fisheries Office are diligently pursuing Asian carp to complete a comprehensive assessment on their movements.
Asian carp are being implanted with radio transmitters in a true life drama of hide and seek. These fish are tracked both manually and with passive acoustic receivers that are placed underwater on buoys and in Lock 19. Researchers are also collecting eDNA samples from Pools 5A, 8 and 9. These samples undergo genetics testing to forensically determine the presence of Asian carp in areas where there are no physical sightings.
Why the fear? The bighead carp and silver carp are Asian species. They are not native fish. They are physically adapted to live in the Upper Mississippi River due to large size, massive body weight, high reproductive potential and voracious appetite. Asian carp invaded the Illinois River more than 20 years ago and now are the most abundant fish species in many areas.
Asian carp began their trek upriver 30 years ago and a thousand miles away. They were imported by commercial catfish farmers in Arkansas in the early 1970s to remove algae from their ponds. Flood waters in the 1980s provided access into the Lower Mississippi River.
Their trek north was assisted by the Great Flood of 1993 allowing expansion into the Middle Mississippi River, Illinois River and Missouri River. Subsequent floods in 1997 and 2001 allowed passage past locks and dams to near Lake Michigan by 2002. The first report of Asian carp in our local Mississippi River waters was 2005 with low numbers currently being caught in nets by commercial fishermen. These carp have been reported as far north as Canada.
Some anglers dream of catching a monster fish. A whopper 73 pound bighead carp estimated to be 20 to 25 years old was caught by a commercial fisherman in lower Sabula Lake in summer 2012. However, hook and line fishermen will be disappointed to know that Asian carp are unlikely to be captured by anglers due to their filter feeding habits. This monster fish was a bad omen of what natural resource managers have feared for many years.
A growing Asian carp population in our local Mississippi River waters is reason for concern not only due to competition with native fish but also a safety hazard to river users. Recreationists on the Illinois River have received broken bones, lacerations, concussions, and knocked unconscious after flying fish encounters. Who would have ever thought that we may one day have to protect ourselves from flying fish?
Ed Britton is a Wildlife Refuge Manager at the Upper Mississippi River National Wildlife and Fish Refuge and a volunteer at Bickelhaupt Arboretum