SEASONAL DISTRIBUTION OF AMERICAN PLAICE ON THE NORTHERN GRAND-BANKS

In 1985 seasonal surveys were conducted on the northern Grand Banks in NAFO Division 3L to determine if there was seasonal variation in the distribution of American plaice Hippoglossoides platessoides Fabricius. Plaice were generally most common between 100 and 200 m depth but were more abundant in depths < 100 m in spring than in other seasons. Fish were under-represented at temperatures greater than + 1.0-degrees-C in all seasons but were much more under-represented at temperatures of -1.2-degrees-C and less, in depths of less than 150 m in winter than in other seasons. There was significant seasonal variation in the geographic distribution of American plaice with the fish being more aggregated in winter than in other seasons. This aggregation was adjacent to an area covered by water of -1.2-degrees-C and less, where few fish were present, and may be related to a greater avoidance of cold water by the fish in winter than in other seasons.