WRC: introducing non-native fish to waters brings consequences

Biologists with the N.C. Wildlife Resources Commission are reminding the public that introducing fish to public waters where they are not native can have irreparable ecological consequences.

Two flathead catfish were found in the river, said Bob Barwick, a district fisheries biologist.

"It's a concern because we know that flathead catfish eat other species of fish that have been enjoyed by anglers. ... There might be a loss of some other recreationally important fisheries in those areas," Barwick said.

Biologists have been sampling the White Oak River since 2001. April was the first time they have found flatheads in the river, which flows along the Jones, Onslow and Carteret county lines in southeastern North Carolina.

Flatheads, which are native to the Mississippi River basin, have been introduced into rivers in the eastern part of the state, becoming well established and abundant within 10 years of being introduced into the Cape Fear, Tar and Neuse rivers, as well as Sutton Lake in New Hanover County, according to information from the WRC.

Since 2006, WRC biologists have been conducting ongoing surveys in the Tar River to document changes in the catfish community as flatheads become established in the system.

In the 2006 survey, flatheads accounted for 14 percent of the catfish population in the Tar River, but in the most recent survey, conducted in 2008, they comprised 56 percent of the total catfish numbers.

In addition to white catfish, flathead catfish are known to eat other popular game fishes, such as largemouth bass, sunfish, crappie, perch and shad, and can have undesirable impacts on these populations. 

Largemouth bass, sunfish, crappie and perch are native to the river, Barwick said.

How the two flathead catfish arrived in the White Oak River is a guessing game.

"We suspect that a well-intentioned fishing person probably released it into the river," Barwick said.

The Wildlife Resources Commission passed a regulation in 2005 that required anyone interested in stocking public, inland water to obtain a stocking permit. The requirement protects native and established aquatic species from the potentially damaging effects of unauthorized stockings by allowing the Commission to assess the impacts of a proposed stocking on a case-by-case basis.

Contact Amanda Hickey at 910-219-8461 or ahickey@freedomenc.com. Read the Lejeune Deployed blog at http://lejeunedeployed.freedomblogging.com.