SEABIRD OBSERVATIONS AT A TIDAL MIXING FRONT IN THE IRISH SEA

Seabird counts were carried out along six transects across a tidal mix ing front in the western Irish Sea using, for the first time, a combin ation of conventional visual bird observation techniques and very high -resolution mapping of frontal structure using an undulating CTD. Four seabird species were clearly aggregated at a precisely defined fronta l boundary. Flocks of seabirds were found to change location over shor t rime periods (hours), maintaining their position relative to the sur face physical parameters and the subsurface thermocline. Results confi rmed considerable anecdotal and limited documentary evidence that sugg est fronts are important feeding areas for seabirds. (C) 1998 Academic Press.