2009 Young-Of-Year Striped Bass Survey Shows Below Average Reproduction
The Maryland Fisheries Service announced that the 2009 striped bass (rockfish) juvenile index, the annual measure of striped bass spawning success in Chesapeake Bay, is 7.9. This is slightly below the average long-term average of 11.7, but more than twice last year’s value. During the survey, biologists identified and counted more than 35,000 fish of 49 species, including over 1,000 young-of-year striped bass.
Variable reproductive success is a normal condition of striped bass populations. Typically, several years of average reproduction are interspersed with occasional large and small year-classes. Large year-classes in successful spawning years like 2003 and 2005 bolster the population by offsetting less successful years. The largest year-class ever measured occurred in 1996.
DNR biologists have monitored the reproductive success of striped bass and other species in Maryland’s portion of the Chesapeake Bay annually since 1954. Twenty-two survey sites are located in the four major spawning systems: Choptank, Potomac, and Nanticoke rivers, and the Upper Bay. Biologists visit each site monthly from July through September, collecting fish samples with two sweeps of a 100-foot beach seine. The index is calculated as the average catch of young-of-year fish per sample. For more information, go to
www.dnr.state.md.us/fisheries/juvindex/index.html.
2009 Young Of Year Index
