Fairly common in a variety of shallow wetlands. Often found in water treatment plants. Usually in small loose groups but can be in larger numbers in suitable habitat. Sometimes feeds in tight packs that move in circles. Bill often swished from side to side as it sieves out food. ID: A large heavy duck, with stonking spatulate bill, that sits low in the water. The bill, combined with short neck and broad head, add to its distinctive bulkiness and should be enough to id most birds. Males unmistakable: bright white accentuates green head and chestnut flanks. Depending on light, head can look purple or black. Females often look pale due to broad fringes to feathers. Bill variably orange with bright edges. Eclipse and young males variable with multiple spots and arrows on breast/flanks with a range of chestnut, white, and green. Ageing males is complicated. Partial face crescent and upperwing pattern similar to BWTE — but always concentrate on size and shape!