By Alex McCrickard/DWR
Striped bass (Morone saxatilis) are one of the most sought-after gamefish along the Atlantic seaboard. Millions of anglers fish for them each year from Maine to the Gulf Coast. In their native coastal rivers, striped bass are anadromous, which means they spend most of their lives in the saltwater environment but return to freshwater to spawn. The Chesapeake Bay is renowned for marine striped bass and the lion’s share of the Atlantic Coast migratory stock is made up of the Maryland and Virginia portion of the bay.
However, in addition to the anadromous striped bass population in the Chesapeake Bay and along the Atlantic Coast, Virginia boasts some of the best inland, land-locked striped bass opportunities you can find in the east. The Virginia Department of Wildlife Resources (DWR) manages these inland, land-locked fisheries. Large impoundments across the state like Smith Mountain Lake, Buggs Island Lake, and Lake Anna to name a few, provide excellent opportunities to target these fish without having to travel to the coast. Managing striped bass in these systems requires a keen understanding of multiple variables—two of the most important being habitat and forage.
Striped bass can thrive in freshwater systems under the right conditions; however, they can’t live in every lake. These fish are a temperate species, requiring cooler water with ample amounts of dissolved oxygen. Warmer weather in the summer months affect both the water temperature and the levels of dissolved oxygen in large lakes.
The thermocline is a thin layer of water that separates the warmer, higher-oxygenated water near the surface and the cooler, less oxygenated, deep water below. Below the thermocline, low dissolved oxygen levels can make life unsuitable for most fish species. Above the thermocline, the water can warm beyond a fish species’ tolerable range. In the summer months in Virginia, striped bass can get pinched out of cool, oxygenated water depending on where the thermocline sets up and the unique hydrology of each lake. Above the thermocline, they can be in water that’s too hot, and below, they might be in water without sufficient oxygen.
“This ‘habitat squeeze’ occurs on Claytor Lake, although the severity can vary year to year,” said Jeff Williams, DWR regional fisheries manager. “In June 2022, an extended period of no rainfall and high air temperatures resulted in a significant striped bass kill on Claytor Lake. Major kills occur about every five to six years on Claytor Lake. However, even in years where significant mortality is not observed, lower oxygen levels can stress these fish, resulting in poor condition and growth.”
It’s important to note that hybrid striped bass, which can tolerate warmer water temperature regimes than pure striped bass, can be an alternative option in fisheries that feature less-than-ideal striped bass habitat. Claytor Lake is also currently stocked with hybrids due to this issue. Ultimately, habitat availability plays a major role in DWR’s management decisions on striped bass impoundments.
Another system that DWR manages with both pure striped bass and hybrids is Lake Anna. “Lake Anna is a wonderful fishery despite the habitat,” said John Odenkirk, DWR fisheries biologist. “Large, adult stripers prefer cool, highly oxygenated water, and that’s just not here.” But the power plant outflow into the lake keeps the water circulating enough that the traditional thermocline, with a warm, oxygen-rich upper layer and cool, oxygen-poor lower level, doesn’t have a chance to form fully in the summer. This provides fish with water quality adequate for juveniles and young adults. Because of the lack of habitat for larger striped bass and resulting slow growth, Lake Anna fishing regulations favor the consumptive striped bass angler with a 20-inch minimum and a four-fish bag per person.
Different regulations are often in effect in systems that maintain exceptional habitat for larger adult striped bass. As an example, the highly oxygenated, cool water habitat at Smith Mountain Lake allows striped bass to grow and thrive at larger sizes. Smith Mountain Lake fishing has high trophy catch potential, and DWR regulations reflect that with a 30- to 40-inch protective slot limit from November 1 through May 31 and a daily two-fish bag per person. From June 1 to October 31, there is no length limit, and this slot doesn’t apply to the two-fish bag due to concerns of catch-and-release mortality during the warmer months of the year.
A strong forage base is essential to a thriving striped bass fishery in an inland system—fish need to eat! All of Virginia’s inland striped bass fisheries are dependent on abundant shad populations. The forage can vary from system to system, but you need an abundance of gizzard shad, alewife, blueback herring, or threadfin shad to satisfy striped bass appetites.
Not all systems with large striped bass are thousands of acres in size. If the habitat and forage align, relatively smaller systems can produce trophy potential. “Waller Mill Reservoir, located in Williamsburg, is only 360 acres in size but has the potential to produce striped bass in the 20- to 25-pound range,” said Scott Herrmann, DWR fisheries biologist. “The strong forage base of gizzard shad within Waller Mill Reservoir allows stocked striped bass to grow to impressive sizes.”
The health and stability of a striped bass population in a water body directly depends on the availability of forage, or shad to eat. This is known as predator-prey balance. A decrease in the population of forage fish often results in reduced growth rates for striped bass and skinny fish. Under these circumstances, malnourished striped bass are much more susceptible to disease and infections. DWR biologists keep close tabs on shad populations and striped bass populations through annual fish population surveys, and that data informs their stocking allotment decisions.
“It’s not a one size fits all deal,” said Odenkirk. “We have to determine stocking rates for each lake individually, because each lake is different based on productivity, the zooplankton populations, and ultimately the forage base populations. We have to find the right mix for each system and the right number of striped bass to stock in each system without crashing the system. You can put in too many predators and the system collapses, leaving no one happy.”
Striped Bass Aquaculture
In addition to keeping tabs on habitat and forage availability, DWR uses aquaculture, or breeding and releasing captive fish, to maintain most inland land-locked striped bass fisheries. While the striped bass fishery at Buggs Island Lake is one of only a few inland, land-locked fisheries with a striped bass population that naturally reproduces successfully, it still needs additional levels of stocking to meet angler demand. “Two of our hatchery facilities raise striped bass: Vic Thomas, which raises Roanoke River strain exclusively, and King and Queen, which raises both Roanoke and Chesapeake strains,” said Brendan Delbos, DWR state hatchery superintendent.
“We stock 10 to 12 waters throughout the state with total production around 1.5 million to 2 million fingerlings per year,” Delbos explained. “While we do see some limited natural recruitment in some of these waters, it’s important to note that striped bass fishing in Virginia impoundments simply would not exist as we know it today without the intervention of our hatchery staff.” Every spring, DWR hatchery staff work long hours collecting large female brood fish and males for transport back to hatchery facilities for spawning. The spawning, rearing, and raising of striped bass is an intensive process, but essential to maintaining our inland fisheries for anglers across the state.
DWR strives to maintain genetic integrity with its striped bass stocking protocols and any inland fishery within the Chesapeake Bay watershed is stocked with Chesapeake Bay-strain striped bass. Other fisheries outside the Chesapeake Bay watershed are stocked with Roanoke-strain striped bass, such as Smith Mountain Lake.
Stocking these reservoirs with striped bass requires more than just pulling up to the boat ramp with a hatchery truck; DWR staff transport the fingerlings throughout the lake to stock them in multiple open-water locations. “Fingerlings are stocked at a size range in which they are still feeding on zooplankton before switching over to feeding on macroinvertebrates and eventually a fish diet,” Herrmann said.