—Craig Springer, for the USFWS, Office of Conservation Investment
The striped bass is a prized catch for anglers, be it at the end of a stout fishing rod or baked and on the plate. They have their following, for good reason. These silvery, thick-shouldered bass reach enormous size, with 20-pounders being commonplace. Anglers catch them on spoons tipped with pork rind or streamers or large top-water plugs fit for muskie fishing. A big striper slamming a floating stick bait will sear a memory into your mind.
These highly sought after fish live along the Atlantic Coast from the Maritime Provinces, around Florida to Texas. Depending on location, they have differing ways of life.
New England striped bass, or as they say around Boston, “stripahs,” migrate up and down the coast and move up big rivers in spring to spawn, going perhaps as far as the first dam. They spawn en masse and the fertilized semi-buoyant eggs incubate as they tumble along downstream without parental care. The spawned-out adults may tarry a bit, but will make their way back to the surf and cruise the coast, an annual event they may repeat five or six times throughout their life.
Further south, below North Carolina’s Cape Hatteras, striped bass take a different approach to reproduction. Though striped bass are wholly comfortable in freshwater, brackish water or saltwater, southern stripers spend their entire lives inland, never going to sea.
And how these southern striped bass spend their days, especially related to spawning, became much clearer thanks to research conducted by fish biologist Jason Marsik with the South Carolina Department of Natural Resources (SCDNR) and his colleague, Dr. Jason Doll at Francis Marion University.
Using Sport Fish Restoration dollars derived from federal excise taxes paid by the manufacturers of fishing tackle and a portion of the federal gas tax that is attributable to motorboats and small engines, the two sought to better understand striper habitat use and movements in the Great Pee Dee River, particularly at spawning time.
Their work added onto prior research into abundance and survival of striped bass, and the success of those spawned at the SCDNR’s Jack D. Bayless Hatchery, and raised at the agency’s Dennis Wildlife Center Fish Hatchery to various sizes and ages at stocking.
Very little natural reproduction of striped bass occurs in coastal South Carolina waters. Populations are maintained by stocking from the SCDNR hatcheries, also supported by Sport Fish Restoration dollars.
Marsik and Doll implanted 10 large, sexually mature striped bass from the Pee Dee River with acoustic transmitters in the abdominal cavity. The biologists relied on 75 acoustic receivers at multiple stationary sites such as bridge pilings and trees from Winyah Bay to the river’s North Carolina headwaters in the Appalachian Mountains. As fish swam by, their presence was detected and recorded on these receivers.
While 10 may seem like a small number of fish to follow, the results show otherwise. Over the three-year study, those adult stripers yielded just shy of 95,000 data points. The acoustic receivers recorded where the fish were, how long they stayed, and their direction of travel. Together, these data helped researchers deduce striped bass habitat preferences.
The mountain of data revealed two significant patterns of movement. One group of fish tended to stay at the bottom end of the river and bay and were never detected moving upstream. One individual wandered nearly 50 miles up the Atlantic Intercostal Waterway. Another group of fish consistently moved up and downstream associated with spawning.
But something was missing—where stripers go in the heat of the summer. A gap in data revealed itself. Marsik believes that Pee Dee stripers ascend tributary streams to find cooler water in the heat of the summer.
“South Carolina fish are resident and can have very stressful summers when the water reaches into the 80-degree range,” said Marsik. “Some fish probably find cooler water in tributaries off the main stem on the Pee Dee, but in a lot of cases there isn’t much food available in the smaller creeks.”
Data gathered on striped bass supported by Sport Fish Restoration informs stocking strategies and regulations to conserve fish. By extension, a data gap points the way where future Sport Fish Restoration work will be directed—uncovering how and where striped bass find refuge in summer. Work on that question starts this autumn.
