The wintering behaviour of coot Fulica atra L. at Cork Lough, south-west Ireland

The activity pattern of a flock of coot Fulica atra at Cork Lough was studied during daylight hours over the winter of 1993/4 using instantaneous scan sampling. As an unknown proportion of the flock was out of sight at any time, the data are based only on visible birds. Swimming was the most important activity of visible birds, representing 38% of daylight hours, followed by feeding (36%). Surface feeding was the main foraging strategy, accounting for about 34% of time spent feeding during daylight hours. There was significant variation in activities both over the day and over the winter. Visible coot spent most of their daylight hours (94.2 ± 0.7%) on water with a temporal variation in the mean percentage numbers being observed. Air temperature had no significant effect on behaviour. Increased precipitation resulted in an increase in resting and a corresponding decrease in the time devoted to preening. An increase in wind speeds was seen to result in an increase in grazing intensity.