White-winged Scoter

February 16, 2019 – Considered a sea duck, White-winged Scoters are observed in numbers primarily along the coastal areas of the US and Canada. They winter along the coastlines from Baja California to the Aleutian Islands in the North Pacific and along the coastal areas of the south and eastern US from the Gulf of Mexico north to the Canadian Maritimes. According to The Cornell Lab of Ornithology online resource, All About Birds, “Although the White-winged Scoter winters primarily along the coasts, small numbers winter on the eastern Great Lakes.”

A solitary bird or just a few are often recorded inland on ice free open areas of lakes and rivers during late winter in Illinois. Higher numbers of scoters will be found across the area of the Great Lakes north into Canada on the migratory staging areas of late winter and early spring as they push towards those summer nesting grounds in the central Canadian provinces, Northwest Territories, and north into central and northern Alaska.

Over the years Jed Hertz has recorded a number of White-winged Scoters on the Kankakee river. This year is no exception. On January 2nd , below the dam near Jeffers park, Hertz spotted a single White-winged Scoter. On Monday February 11th Jed again found a duck that could actually be the same scoter on the river east of Aroma Park. Photos allow for a closer look of the scoter and it appears to be an immature drake. Jed notified me and I was able to get a few shots of the duck as it worked on an aquatic plant stem, biting and chewing it between its’ thick bill, possibly trying to remove a larvae from the hollow parts of the segmented stem.

White-winged Scoters are a diving duck that feed mainly on mollusks. In wintering areas, crustaceans are an import food source. Scoters have a unique ability to use their wings and feet to propel quickly to the bottom. I observed this behavior from my vantage while watching three scoters feeding near 4th avenue in Kankakee in January of 2014. When they began their head first dive their wings became partially opened and used as if in flight as they disappeared into the depths. A science journal article called “Costs of diving by wing and foot propulsion in a sea duck, the white-winged scoter”, states that, “Most birds swim underwater by either feet alone or wings alone, but some sea ducks often use both.”, perhaps an adaptation required for deep water dives. ”Scoters using wings + feet had 13% shorter descent duration, 18% faster descent speed, 31% fewer strokes/m, and 59% longer bottom duration than with feet only.” J Comp Physiol B. 2008 Mar;178(3):321-32. Epub 2007 Dec 7.