Invasive carp found in James River in ND
North Dakota Game and Fish Department confirmed the presence of silver carp in the James River Wednesday.
The species is known for destroying habitat and injuring boaters.
Surveys by fisheries officials found an 18-inch long, 2.4-pound silver carp in the waters of the tailrace, the river segment directly below the Jamestown Dam Wednesday. The survey was prompted when an angler caught a silver carp from the James River near LaMoure, N.D., earlier this month.
Silver carp were originally brought to the United States as stock for fish farms. In the 1970s some fish escaped into the Mississippi River system and have since spread through much of the Mississippi and Missouri rivers systems although they had not been seen in North Dakota until now.
"Obviously this is undesirable," said Gene Van Eeckhout, district fisheries supervisor in Jamestown. "We need to be careful so it doesn't spread."
The fish have become more prevalent all along the James River.
"In South Dakota this is the year we've been finding a lot of silver carp," said Cari-Ann Hayer, fisheries researcher at South Dakota State University. "We've found about 100 in the South Dakota portion of the James this year alone."
Hayer said the fish have ranged from fingerlings which might be this year's spawn to older fish of up to 20 pounds.
"We're still studying how they reproduce and growth traits in the James," she said. "We don't know a lot about these fish here yet."
Local officials believe a fish or two in the river could be the leading edge of a growing problem.
"Eventually there will likely be more," said B.J. Kratz, fisheries biologist for the Game and Fish Department in Jamestown. "But there always has to be a first."
Kratz was part of a crew of fisheries workers electro fishing several stretches of the James River during the past few days. The process uses a gas-powered electric generator to charge a probe mounted on a pole in front of the boat. The electric current stuns the fish, which briefly float to the surface. Crews net the fish for identification and return them to the water.
Officials used the process to survey the waters near LaMoure and below Pipestem Dam without finding any silver carp before testing the waters below Jamestown Dam.
"The silver carp consumes plankton," Kratz said. "This is at the bottom of the aquatic food pyramid so its presence does damage all the way up the food chain."
The fish is also known for jumping out of the water in the path of approaching boats or water skiers.
"Jumping in front of boats becomes a factor if the density becomes high enough," Van Eeckhout said.
Van Eeckhout said Game and Fish crews had been electro fishing the area near Ludden, N.D., every fall since the fish was discovered near Huron three years ago. Fisheries scientists have assumed that the silver carp will continue to expand its range.
"We're lucky here," he said. "The two high dams will stop the fish from naturally moving into the Pipestem and Jamestown reservoirs and I don't think people would intentionally carry them across."
The find will likely lead to additional regulations concerning bait fish in the area. The silver carp fingerling looks similar to some of the sucker and minnow species commonly used for bait.
"The first thing is, don't use bait fish from the James River," Van Eeckhout said. "There may be regulations concerning that coming down."
"That's about all we can do for control," she said. "There isn't much you can do but try to keep them from spreading to new waters."
Another area lake may also face problems with silver carp.
"The concern would be Spiritwood Lake," Van Eeckhout said. "If the water is high enough the fish could work through Seven-Mile Coulee and Alkaline Lake into Spiritwood Lake."
Van Eeckhout said he hoped further electro fishing surveys of the river could be done when levels fall after releases from the Jamestown and Pipestem dams are reduced later this month.