Offshore Distribution, Size, Age, and Lateral Plate Variation of Late Larval/Early Juvenile Sticklebacks (Gasterosteus) off the Atlantic Coast of New Jersey and New York

Abstract

Late larval and early juvenile sticklebacks, Gasterosteus aculeatus (14–28 mm SL) and G. wheatlandi (11–19 mm SL), were collected over shelf waters in the New York Bight during May, June, and July 1988. Gasterosteus aculeatus occurred up to 110 km offshore, with peak abundances found from 3 to 75 km. Gasterosteus wheatlandi was most prevalent within 10 km of shore, but some individuals were collected up to 55 km offshore. The further offshore distribution of G. aculeatus should increase its potential for dispersal, perhaps explaining their capacity to found freshwater populations in recently deglaciated habitats. The relatively nearshore distribution of G. wheatlandi should minimize dispersal (especially around Cape Cod) and may maintain a distinct, morphological step cline by the relative isolation of two subpopulations above and below Cape Cod.