Chesapeake Bay Shad Populations

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Shad abundance has surged in four Chesapeake Bay rivers, surpassing the restoration goals set by the Chesapeake Bay Program in the Potomac and Rappahannock.

The Bay Program tracks the abundance of American shad in the James, Potomac, Rappahannock, Susquehanna and York rivers as an indicator of watershed health. Collectively, these five waterways account for about 90 percent of the Bay’s shad population, and each has its own population target.

Between 2000 and 2014, shad abundance in the Bay increased from 11 percent to 44 percent of the goal. In 2014, abundance in the Potomac and Rappahannock reached 130 and 110 percent of the rivers’ respective targets.

Scientists attribute the increases to a series of factors, including improvements in water quality; a resurgence in underwater grass beds; moratoriums on shad harvest; an increase in habitat available to migratory fish, thanks to the installation of a fish passageway in the Potomac and the removal of the Embry Dam on the Rappahannock; stocking efforts that reprint fish to rivers and kick-start local populations; and the overall suitability of the Potomac, in particular, as shad habitat. Historic records document a remarkably productive shad fishery in the Potomac, which indicates the river’s potential for producing shad is extremely high.

Chesapeake Bay American Shad Facts

Between 2000 and 2014, American shad abundance in the Chesapeake Bay increased from 11 percent of the goal to 44 percent of the goal.

Shad abundance in the Potomac River has steadily increased, and in 2011 surpassed the target. Between 2013 and 2014, abundance in the Potomac rose from 127 to 130 percent of the target.

Shad abundance in the Rappahannock River has varied, reaching 90 percent of the target in 2003 and 2004, falling below 30 percent of the target in 2010 and reaching 93 percent of the target in 2012.

Between 2013 and 2014, abundance in the Rappahannock rose from 89 to 110 percent of the target.

Shad abundance in the York River has varied, reaching 74 percent of the target in 2001 but remaining below 40 percent of the target between 2005 and 2013. Between 2013 and 2014, abundance in the York rose from 23 to 58 percent of the target.

Shad abundance in the lower James River has fluctuated between 4 and 27 percent of the target. Between 2013 and 2014, abundance in the lower James rose from 13 to 21 percent of the target.

Shad abundance in the upper James River has remained negligible. Between 2013 and 2014, abundance in the upper James remained below one percent of the target.

Shad abundance in the Susquehanna River has remained negligible. Between 2013 and 2014, abundance in the Susquehanna remained below one percent of the target.

source: Chesapeake Bay Program

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