 Southlake Moor is unusual in that, when conditions in the River Parrett are suitable, it may be deliberately flooded in winter by means of a sluice in the river floodbank.Some 96 species of aquatic and bankside vascular plant species have been recorded from Southlake Moor, of particular interest is the greater water-parsnip ("Sium latifolium").When the moor is flooded, large numbers of wildfowl may be present; with up to 22,000 wigeon ("Anas penelope"), 250 Bewick's swan ("Cygnus bewickii") and good numbers of pochard ("Aythya ferina"), teal ("Anas crecca") and tufted duck ("Aythya fuligula").