COPEPOD AND BARNACLE NAUPLIUS DISTRIBUTIONS IN THE IRISH SEA - RELATION TO SPRINGTIME HYDROGRAPHIC VARIABILITY

The distributions and abundances of copepod and barnacle nauplii are d escribed along a five-station transect in the Irish Sea from Liverpool Bay, England, to Dundalk Bay, Ireland, in May 1989. Correspondence an alysis revealed that various hydrographic regions in the Irish Sea are characterized by distinct nauplius assemblages. Acartia, Centropages and Temora nauplii were associated with the Welsh coastal water east o f the Liverpool Bay front. The western stratified water to the west of the seasonal, western Irish Sea front was distinguished from the mixe d water to the east by abundances of Calanus, Pseudocalanus, Oithona M icrocalanus and harpacticoid nauplii. The Liverpool Bay and western Ir ish Sea fronts are, apparently, boundaries between coastal and offshor e assemblages of crustacean nauplii.