A hungry species of carp will be introduced to Stafford County’s Lake Mooney in May to help combat hydrilla, an invasive aquatic weed that can cause economic and ecological damage.
County officials are working with the Virginia Department of Game and Inland Fisheries to determine the number of grass carp needed to allow natural vegetation to thrive, while keeping the hydrilla growth in check.
Grass carp “have a way of widely opening their mouths, ‘inhaling’ a gob or long strand of vegetation, and chomping down. ... They are eating machines,” stated a June 2018 article in Outdoor News.
Hydrilla is an aggressive plant that dominates surrounding natural growth in the water, pushing out native species.
The plant, which can be found in lakes, ponds, and rivers, has slender, branched stems that can grow up to 25 feet long. Hydrilla can grow to the surface of the water, where it forms dense mats.
For now, Stafford officials ask residents to release any grass carp caught in the lake to allow the fish time to become acclimated to their surroundings and begin managing the weed growth effectively.
Grass carp have no barbels, the whiskerlike sensory organs near the mouths of some other carp varieties. The fish are olive-brown in color on the dorsal side, with silver sides and a white belly, and their scales are large, with dark edges.