The annual young of the year (YOY) survey results are in, and, well, they are not great, but they’re not that bad either. Don’t get me wrong, this isn’t the end all, be all of the future of striped bass that some make it out to be when the survey comes in overly high or low, but it is an indicator of the potential of future fish stocks.
A great reproduction year can easily be wiped clean by an almost innumerable amount of natural and man-made obstacles, but it is a start. Conversely, a low reproduction year can be corrected when the planets align and things go right for those little fish for several consecutive years of their growth and development.
Each year several coastal Atlantic states conduct seine surveys in their waters for a variety of fish species. When tracked from year-to-year, we get a good idea of how successful or unsuccessful the year-class will be. The idea here is that you begin each year with a finite amount of fish in the sea, and from there the population base can be estimated.
The most popular, or at least the most commonly referenced survey when it comes to striped bass, is the one conducted by the Maryland Department of Natural Resources, Fisheries Service. This year’s YOY index came in at 14.8. This is a little bit above the 65-year average of 11.8; it follows last year’s above-average index of 13.2 in 2017, and an abysmal index of 2.2 in 2016. In 2015, the second-highest index ever recorded—a whopping 24.2—had anglers up and down the coast rejoicing the fish Gods—oh how fleeting those cries of joy turned out to be the following year. What this shows is that year-to-year things can fluctuate, sometimes doing so quite wildly. Many factors go into the results including warm winters and dry springs.
And while those conducting the survey do a good job of including a wide sampling, there is simply the factor of chance which weighs-in on the results—it’s a cloudy science by any extent of the imagination.
Nonetheless, the following, which were announced this week by the Maryland Department of Natural Resources and the Virginia Institute of Marine Science, give us an idea of what kind of baby striper population is swimming around out there right now.
CHESAPEAKE BAY SURVEY FINDS HEALTHY STRIPER REPRODUCTION
The Maryland Department of Natural Resources announced results of its annual young-of-year striped bass survey in Chesapeake Bay, which documented healthy reproduction of the state fish. The 2018 young-of-year index is 14.8, higher than the 65-year average of 11.8.
Known locally as rockfish, striped bass spawn in Chesapeake Bay and its tributaries each spring. The juvenile striped bass survey is conducted annually to measure spawning success and help predict future abundance. The index represents the average number of young-of-year – those hatched in the current year – striped bass captured in each sample.
During this year’s survey, department biologists collected more than 36,000 fish of 55 species, including 1,951 young-of-year striped bass. Results show that white perch and American shad also experienced above-average spawning success this spring.
“Consecutive years of healthy reproduction is a great sign for the future of this iconic species,” Fishing and Boating Services Director David Blazer said. “The survey results are encouraging and complement our efforts to conserve and protect the striped bass fishery throughout the watershed for the benefit of anglers, commercial watermen and the species.”
The department has monitored the reproductive success of striped bass and other fish species in Maryland’s portion of Chesapeake Bay annually since 1954, making it one of the oldest fish community surveys in the nation. Twenty-two survey sites are located in the four major spawning systems: Choptank, Potomac and Nanticoke rivers and Upper Chesapeake Bay. Biologists visit each site three times during the summer, collecting fish with two sweeps of a 100-foot beach seine net. The fish are evaluated for age, size and other factors, and then returned to the water.
JUVENILE STRIPED BASS MAINTAIN AVERAGE ABUNDANCE IN VIRGINIA
Preliminary results from an ongoing long-term survey conducted by researchers at the Virginia Institute of Marine Science suggest an average year class of young-of-year striped bass was produced in Virginia tributaries of the Chesapeake Bay in 2018. The 2018 year class represents the group of fish hatched this spring that can grow to fishable sizes in three to four years, if not claimed by natural mortality.
The program, formally known as the Juvenile Striped Bass Seine Survey, recorded a mean value of 10.72 fish per seine haul in the Virginia portion of Chesapeake Bay, which is similar to the historic average of 7.77 fish per seine haul. The 2018 value—which scientists call a recruitment index—was also similar to indices observed in the past five years. Although there can be considerable variation in striped bass recruitment among years, the average indices observed in recent years suggests that abundance of juvenile striped bass has been stable.
Striped bass play an important role as a top predator in the Chesapeake Bay ecosystem and are a valuable resource for commercial and recreational anglers. Professor Mary Fabrizio, who directs the Juvenile Striped Bass Seine Survey at VIMS, notes that the economic and ecological value of striped bass lends significant interest to the year-to-year status of their population. "By estimating the relative number of young-of-year striped bass," she says, "our survey provides an important measure of annual and long-term trends in the Bay’s striped bass population."
The VIMS Juvenile Striped Bass Seine Survey currently samples 18 index stations in the Rappahannock, York, and James River watersheds. Biologists sampled each site 5 times from late June to early September in 2018, deploying a 100-foot seine net from the shore. Each fish captured in the net is counted, measured, and returned to the water. These young striped bass usually measure between 1.5-4 inches long. Survey scientists in Virginia measured 1,875 juvenile striped bass at these stations in 2018. VIMS has been conducting the survey annually since 1967 for the Virginia Marine Resources Commission (VMRC). The Maryland Department of Natural Resources conducts a similar survey in the northern portion of the Bay.
The striped bass population in the Chesapeake Bay has rebounded from historic lows in the late 1970s and early 1980s, after fishing bans were enacted in Delaware, Maryland, and Virginia in the mid- to late-1980s. Since then, the population has increased to the point that striped bass in the Bay and elsewhere are now considered recovered. Monitoring of juvenile striped bass recruitment will continue next year to provide managers with crucial information to sustainably manage this important species.
