Surf Scoters breed on inland lakes but winter on the coasts, and migratory movements take place at night. When diving underwater, the behavior of Surf Scoters is variable. Sometimes they propel themselves with their feet alone, sometimes they extend their wings to help steer, and sometimes they propel themselves with both wings and feet.
Until near the end of the 20th century, very few studies of breeding Surf Scoters had been conducted, making it one of the most poorly studied species. Surf Scoters are thought to breed for the first time at age two or three, but little information exists as to their maximum lifespan.
Description of the Surf Scoter
Male and female Surf Scoters are substantially different in appearance.
Juvenile males resemble females but have a distinctive bill shape. The front of the head and the bill give a sloped appearance in adult males.
BREEDING MALE
The Surf Scoter is a large sea duck with a large bill. It varies in appearance based on gender.
Males:
-Black with a white forehead and nape.
-Multicolored bill.
Female
Male vs female
Multicolored bill and white patch on the back of the neck and the forehead make this adult male Surf Scoter an easy bird to identify. The white eye in the adults is not always apparent. Photograph © Greg Lavaty.
Young male has some orange starting to show on the bill. Photograph © Tom Grey
Adult female Surf Scoter. The white vertical mark at the base of the bill is variable, and often stronger. See the pair on the last photograph on this page. Photograph © Tom Grey.
First winter female Surf Scoter. Photograph © Tom Grey.
Male and female Surf Scoters. The vertical white mark at the base of the bill on the female is a good mark for an adult female. Photograph © Greg Lavaty.
Dark cap and bumpy bill indicate juvenile male.
Wings produce a low whistle on male. Photograph © Glenn Bartly.
Surf Scoters migrate along both coasts. Photograph © Glenn Bartly.
Bill markings on the bird on the left indicate Surf Scoter. Photograph © Greg Lavaty.
Seasonal change in appearance
Limited changes.
Juvenile
Juveniles resemble females.
Habitat
Tundra lakes, oceans, and bays.
Diet
Mollusks and aquatic invertebrates.
Behavior
Forages by diving.
Range
Breeds from Alaska to eastern Canada and winters along both coasts of North America.
Fun Facts
Broods of young occasionally intermix, resulting in apparently large broods with one female.
Males defend an area around a female rather than defending a territory.
Vocalizations
Usually silent.
Similar Species
- White-winged Scoters have white wing patches, and female Harlequin Ducks have much smaller bills.
Nesting
The nest is a depression on the ground.
Number: 5-9.
Color: Buff.
Incubation and fledging:
– Young hatch at 28-30 days.
– Young fledge (leave the nest) shortly after hatching.
Conclusions
Surf Scoters exhibit interesting behavior in their breeding and wintering patterns. They breed on inland lakes, but during winter, they relocate to the coasts. Interestingly, their migratory movements predominantly occur at night. When it comes to their underwater diving behavior, Surf Scoters display variability.
Sometimes, they rely solely on their feet for propulsion, while other times, they extend their wings to aid in steering. There are instances when they use both their wings and feet to propel themselves underwater.
Remarkably, until the late 20th century, very few studies were conducted on breeding Surf Scoters, rendering them one of the most poorly researched species. The age at which they first breed is believed to be around two or three years, but limited information is available concerning their maximum lifespan.