The recent annual carp removal by the Kansas City and Northwest Region of the Missouri Department of Conservation and the U.S. Fish and Wildlife Service was conducted for the first time on the Platte River.
The carp removals have been done in previous years on larger bodies of waters, such as the Lamine River and the Grand River to find out if similar methods work on smaller waterways such as the Platte River.
“The goal is to establish data showing what methods work best to come up with a longer-term management plan,” Erin Woodiel, Media Specialist at MDC Kansas City and Northwestern Regions said. “While we know a single round of intensive removal won’t totally eliminate invasive carp from any water, reducing their population by any amount is a positive step.”
Invasive carp disrupt the food web, dominate over native species for resources and threaten Missouri waters.
Silver carp lay hundreds of thousands of eggs and have a reproductive strategy of ‘more is more’. This strong breed of fish survive in a variety of conditions where some native wildlife cannot.
“When they grow large and are numerous, they end up taking all the food sources, mainly plankton, that many of our native fish need to live,” Woodiel said.
Carp also pose a threat to fishermen and boaters.
“While we don’t keep any formal reports or records of injury from fish jumping out of the water, they certainly pose a safety threat,” Woodiel said. “I was out on the water for only an hour and had several jumping around me, even getting hit in the head by one. They come out of nowhere and jump in a seemingly random direction, so it definitely can be dangerous to have projectiles coming at boaters like that.”
September was chosen as one of the best times for carp removal, since this time of year has more stable water levels and cooler water temperatures than mid-summer. This helps keep the schools of fish from moving a lot. Woodiel also said it’s a good time of year to minimize the impact on public use of the water because access point have to be closed off.
Several dozen MDC staff members came out to pull carp out of the water for eight days in September. More than 8,000 pounds were pulled out each day. This intensive removal has a goal of removing at least 40,000 pounds of carp. The number of carp removed each year varies based on what location the removal is targeting, and the conditions.
Several different methods are used to remove invasive carp including electrofishing, where charged rods are put into the water creating an electric field that temporarily stuns the fish, giving staff time to scoop them up with nets.
“Another method is gill netting,” Woodiel said. “Staff drop long nets across the waterway and wait for fish to swim into them. Then, the nets are pulled back into the boat. Carp are kept, and any accidental catches of other species are released back.”
After the fish are caught, MDC and the U.S. Fish and Wildlife Service gives them to a commercial fishing operation for processing so the fish don’t go to waste. The Platte River fish were processed by the Missouri Coast Fisheries. They preserved as many useful parts as possible to make fishing bait, dog treats and other products in order to minimize waste. They hope to offer future products that include more elements of the carp. Invasive carp can deplete the number of native species, negatively affecting commercial fisheries. The commercial fisheries that do process carp, like Missouri Coast Fisheries, see it as an opportunity to turn something harmful into something useful.
“The days out on the boats can be fun,” Woodiel said. “I joined on one of three electrofishing boats coordinating their efforts to maneuver fish into ideal areas to be caught. You have to keep your wits about you, because carp will be jumping out of the water and it’s very likely that they will hit you, or jump into the boat next to you, in the process. Silver carp have an instinctive response to jump out of the water when they are disturbed, such as when they hear the motor of a boat approaching in the water. It’s a challenge to use long nets on poles to catch these fish as they come to the surface, either as they jump, or as they are temporarily stunned. Everyone ends up pretty muddy and a little bit slimy from handling the fish, and it’s a lot of physical effort to be lifting them over the edge of the boat for so many hours. Our crews on Tuesday even started out in the rain. We don’t let weather stop us.”
MDC continues to look for different ways to tackle the problem of invasive carp. They are taking a close look at how these annual removals impact fish populations by decreasing invasives and increasing native species
Woodiel said that one of the particular challenges in Missouri is that the waterways are very open and very interconnected. It’s very easy for fish, both native and invasive, to travel from one river into another, making it harder to contain fish to any particular area.
“MDC understands that complete eradication of invasive carp is unlikely,” Woodiel said. “Our main efforts are going to slowing their expansion and limiting their impact on native species. This is an ongoing effort that does involve people from all across the state. Getting data from multiple waterways is important for understanding how management strategies may work across the state.”
The most common way for invasive carp to reach a lake is anglers carrying them in water-filled bait buckets onto a lake to use as live bait. The carp can escape from hooks, plus unused bait is often dumped into lakes when fishing ends. “Anglers should use caution when using live bait in any lake or river, including small community lakes,” Woodiel said. “Unused bait from any source should be contained and put into the trash rather than dumped into the water. And if an angler happens to catch an invasive carp while fishing, they should keep it. These fish are absolutely edible, and it’s much better to take it out of the water than return it.”
