Mallard vs White-winged Scoter

Female gives the classic 'quack-quack-quack', descending in pitch. Male utters soft nasal 'raeb-raeb'. Both give a high 'gag-gag-gag' when alarmed or taking flight.

Male produces a soft, whistled note; female gives a harsh, grating call. Similar to Velvet Scoter; the female's rasping call carries across North Pacific bays and coastal inlets.

Breeding males have an iridescent green head, white neck ring, chestnut breast, and grey body. Females are mottled brown. Both sexes show a blue speculum bordered by white.

Broad, flat bill — yellow-green in males, orange-brown in females

Male is black with conspicuous white secondaries and a white comma-shaped mark below eye; orange-yellow bill with black basal knob. Female dark brownish-black with two pale facial patches and white …