Life History and Population Dynamics of the Bay Anchovy in New Jersey

All life stages of the bay anchovy Anchoa mitchilli were sampled intensively in Barnegat Bay, New Jersey, during 1975–1981. This species was the most abundant trawl-susceptible fish, accounting for 52% of the catch, with peaks in abundance occurring during May and June and again in September and October. Seasonal movements appeared to be correlated with seasonal changes in water temperature. Adults moved into the estuary in the spring, and an offshore and southerly emigration from the estuary to continental shelf wintering grounds occurred in the fall. Spawning began as early as April and peaked in June and July; some eggs were found as late as November. Larvae first appeared in May of each year, were most abundant in July and August, and were rare after October. Ichthyoplankton samples were dominated numerically by bay anchovy eggs and larvae, accounting for up to 98 and 56% of the annual egg and larval catches, respectively. Significant annual fluctuations in the abundance of all life stages were documented. Population levels of the bay anchovy in New Jersey waters appear to be regulated largely by the survival rate and migratory patterns of the overwintering population and to a lesser degree by events occurring within the estuary during the first few months of life.