During the last few years, the number of grey seals in the Sable Island breeding colonies has increased. The expanding colonies occupy ever- larger areas, thus reducing the amount of beach which can be surveyed during December and January. Seaweed, storm waves, slush and seals all affected the 1993-2002 survey schedule. In order to carry out surveys in conditions which permitted a thorough search, the schedule was often adjusted by a week or so - surveys were done usually once every 35 to 45 days.