Evaluating restoration efforts of American shad in Virginia

Fisheries for American shad in the Virginia waters of Chesapeake Bay have been under moratorium since 1994.  An offshore mixed-stock fishery operated beyond 1994, but chronic low abundances of American shad within many Atlantic coastal states prompted closure of that fishery in 2005.  Although juvenile abundances have been monitored in Virginia since 1980, in-river sampling of adult fish did not begin until 1998.  Current stock status of adult American shad is being evaluated through a cooperative effort with commercial fishers who capture fish using traditional methods in three Virginia rivers (James, York, and Rappahannock).  Current catch-rates are compared to those recorded in logbooks completed voluntarily by fishers prior to fishery closures under the notion that historical catch-rates represent conditions of healthier American shad stocks.  Here we provide results of a comprehensive analysis of the available adult and juvenile American shad monitoring data in Virginia.  We compare several computational forms of juvenile and adult abundance indices, test hypotheses regarding the role of various environmental variables on American shad catch-rates, evaluate the relationship between measures of juvenile and adult abundance, and assess the influence of hatchery inputs. The estimated trends in abundance are discussed in the context of target restoration levels.