If there is one common theme across Virginia right now concerning our fisheries, it is the threat that non-native species present to our long-established gamefish. DWR Region 1 Fisheries Manager Clint Morgeson details the danger that the blue catfish presents in the Tidewater region.
“Blue cats were stocked by the then-Game Commission in the 1970s as a response to the collapse of the striped bass population in the Chesapeake Bay Watershed,” he said. “They are a major threat to our blue crabs and a small percentage of their diet is made up of our river herrings. As voracious omnivores, blues no doubt have had a negative effect on our native bullheads and white catfish, as well as some impact on our imperiled sunfish species.”
Alex McCrickard, DWR’s aquatic education coordinator, explained one way to approach blue catfish. “Blue catfish are ubiquitous in Virginia’s tidal systems and are readily available for anglers to target and catch,” said McCrickard. “In an effort to mitigate against this species’ negative impacts, DWR advocates for the harvest of blue catfish following Virginia Department of Health consumption advisories. And it just so happens that they are great eating, especially when battered and lightly fried.”
Another problem species is the northern snakehead, which were released by an unknown individual or individuals into the Potomac in the early 2000s. They have now made their way southward into Tidewater.
“Snakeheads have not had as negative of a threat as was feared on Potomac largemouths so far,” Morgeson said. “But the Mattaponi and Pamunkey rivers are not the same as the Potomac; every watershed features unique characteristics. It’s possible that snakeheads ran into the bay and then into the Pamunkey, but it’s also possible that they were released. One of our biggest fears is that snakeheads could wind up in the James.”
Yet another scourge is the Alabama bass, known by many as Alabama spotted bass, which an unknown angler or anglers introduced into Diascund Creek Reservoir and were first detected in 2009. Alabama bass have now made their way into the Chickahominy, and, like the snakehead, state fisheries biologists worry that they could become firmly established in the James. Extensive genetic testing by DWR led to detections of Alabama bass in other waters including Lake Gaston, Buggs Island Lake (Kerr Reservoir), Claytor Lake, the New River below Claytor Lake, Philpott Lake, and Martinsville Reservoir in addition to the fall line section of the James River in downtown Richmond.
Morgeson related that the DWR understands the appeal of Alabama bass as they are popular with some anglers who find them aggressive and easy to catch. However, any fishery in any state can only support so many gamefish, and Alabama bass have a well-documented history of negatively impacting largemouth and smallmouth bass fisheries.
“Many systems have lost their trophy largemouth potential after the introduction of Alabama bass,” said McCrickard. “Interspecific competition, specifically for food and habitat, gives Alabama bass an advantage over largemouth bass.”
Equally concerning are the impacts Alabama bass pose to smallmouth fisheries.
“Alabama bass have been shown to wipe out smallmouth populations through introgression,” McCrickard said. “Continued hybridization and backcrossing allow Alabama bass to genetically swamp smallmouth bass. With continued concerns over our smallmouth bass populations in Virginia, the last thing these fish need is a species that could threaten them genetically. Unfortunately we are already seeing hybridization occurring in systems like Philpott and Claytor.”
DWR biologists are also concerned about the recent appearance of hybrid stripers in Lake Chesdin.
“One of Virginia’s most prized and popular fisheries is the James River strain of native striped bass,” Morgeson noted. “When we release striped bass into the James watershed, we take great pains to make sure those fish come from James brood stock so that if they leave that particular body of water there won’t be any negative effect on existing populations.
“Hybrid stripers greatly complicate that management goal. Yes, hybrids are sterile, but that doesn’t stop them from trying to mate with our native stripers, which can result in a wasted spawn.”
Solutions to these issues?
“Don’t release non-native gamefish or bait into your local waters,” Morgeson emphasized. “If you see or hear of someone else doing so, please report it to DWR. Also, catch and keep non-native fish. Blue cats and snakeheads, for example, have well-earned reputations as being excellent table fare.”