Research Product

A categorical time series regression model was developed to evaluate the importance of natural and anthropogenic environmental changes to the determination of white perch stock abundance in the Choptank River, Maryland. Ninety-one percent of the variability in historical stock size for the period 1929-1985 could be explained by a combination of April and May freshwater discharge level, parental stock size, and sewage loadings lagged 2-3 and 9-10 years. Clearly most of the annual variablity was associated with changes in natural environmental factors, but a significant, albeit, small portion of the variability in stock size was attributable to sewage loadings in the Choptank River.