Aspects of the Biology of Ammodytes americanus from the St. Lawrence River to Chesapeake Bay, 1972-75, Including a Comparison of the Long Island Sound Post larvae with Ammodytes dubius

Abstract

Juvenile and adult Ammodytes americanus, ranging in length from 49 to 235 mm, were collected in 1972-75 between the St. Lawrence River and Chesapeake Bay. Those from inshore tended to be younger than those from offshore and the zero year-class by the end of the first year ranged in length from 80 to 115 mm. Weight increased isometrically, with variations between geographical areas and between seasons of the year. An inter-specific cline in meristic index was evident between A. americanus and A. dubius, and an inshore-offshore intraspecific cline occurred within the range of A. americanus. Post larval A. americanus from Long Island Sound differed in pigmentation from A. dubius from the Scotian Shelf. A. americanus rapidly developed a solid line of stomach pigment, but preanal, supradorsal and subdorsal melanophores, prominent in postlarval A. dubius, developed more slowly in A. americanus.