Large Gatherings of Peaks Island Sea Ducks
"The Players"
Common Eider (Male right)
Common Goldeneye (Male)
Bufflehead (Male left)
Red-breasted Merganser
(Male)
Photo © Andrew Jackson
Long-tailed Duck (Males left)
Harlequin Duck
(Rare – seen one time this winter by Sam Wainright)
(Male in Center)
The "Story'
Peaks Island sea ducks abound along the shore this winter and spring. Currently several species are ‘fattening-up’ for their long migration journey to the North, or have already departed. Most of the Common Eiders, however, will stick around for the breeding season.
Sea ducks cannot soar; they rely instead on rapid beats of their smallish wings. During migration some species fly high in large flocks (e.g. Black Scoters), taking advantage of stronger winds found there (1). Others may fly in small groups.
Flying Black Scoters
Most recently large numbers (100 to > 350) of Black Scoters have joined forces with the Common Eider flocks around Peaks Island. Perhaps the Black Scoter flocks are taking advantage of a ‘safety in numbers’ with the Common Eiders? Over the winter, groups of Black Scoters seen along the shore rarely reached 100 individuals. Where did these new scoters originate – perhaps somewhere south of here? Is Peaks Island a temporary ‘fueling’ station in route to their breeding grounds on rocky-shored lakes and ponds in the boreal forest/tundra zone of northern Quebec, Labrador, and eastern Hudson Bay (3).
These large numbers of scoters and eiders are merging into what appears as a sea-duck ballet. You may see them in a large roundish raft, only to morph into random shapes, before scurrying off into a long alignment either heading off coast or close to shore where they feed and ‘surf’ the waves. Kathy described their flight, after being disturbed by a fishing boat, as ‘murmurations’ similar to starlings (4).
Common Eider and Black Scoter Flock
Flock Morphing
'Linear' Flock
'Surfing' Black Scoters
Black Scoters and Common Eiders both search for bottom-dwelling invertebrates (mostly mussels, clams, and crabs) on the sea floor. The foraging behavior of the Black Scoter is more synchronized than the eiders that may dive independently of each other. In a very large flock of over 100 scoters, the birds appear to peel-off and dive in a flowing fashion – think of synchronized swimming. But, what are the scoters doing underwater? Wouldn’t ~ 100 scoters make for a crowded place down there? Are there any collisions?
Black Scoters - Up
Now They Are Down
At night, these mixed flocks of eiders and scoters head offshore for their nightly repose forming either predictable, nicely formed large rafts – or sometimes it appears unpredictable where they form long lines or several disorganized rafts. They may intermingle, or segregate within the flock by species.
Mixed Flocks of Eiders and Scoters
Segregated Flock of Eiders (left) and Scoters (right)
How far out to sea do the eiders and scoters travel for safety? It is perhaps weather dependent. With offshore winds, will they venture into those heavy seas far from shore, or stay closer to shore with less wind and wave action. I have observed their rafts spreading out linearly at what appears the interface between relatively calm waters and the ‘high-seas’. Observing where they ‘sleep’ with onshore winds is unknown.
Sleeping Choices
Where do they go when the storms roll through Peaks Island?
Years ago Peggy asked, “Why do the eiders stay in large rafts?” And Carol noted that the Emperor Penguins (‘March of the Penguins’) in the Antarctic winters huddle in groups, each individual taking a turn on the periphery where it is most exposed to the cold. Do the eiders and scoters, especially at night when they travel out to sea together, huddle close enough to gain some warmth from each other? Or an individual in a crowd (think fish schools) is less likely to become a predator’s meal. I have observed the eider flocks get agitated to the point of panic when a loon is prowling about (Subsurface loons have been known to come from beneath, and then ‘spear’ another loon - territoriality issues? [2]).
A Harbor Seal will send the eiders into an absolute frenzied panic – propelling themselves over the water, 'bellying-up' to the rocks, and scrambling to safety. Or is ‘rafting’ part of their social structure? Rafts may provide more eyes to find the best feeding spots, or better opportunities for finding a partner? Perhaps rafting serves all of above, and more?
But, what about the other sea ducks? They are equally as splendid and interesting, even if there are fewer of them. Two more striking scoter species are here and ‘itching’ to migrate – the Surf Scoters (breed in northern Quebec, Labrador, and Hudson Bay area) are showing some signs of early courtship displays.
3 Male Surfscoters and 1 Female Surfscoter (middle)
Displaying Male Surfscoters; Female in the Middle
'All Bets Are Off'; Female (in the lead) Flies-Off
The White-winged Scoters are more elusive and perhaps some have already started their journey north, as we see very few in March.
3 Male and 1 Female (To the right) White-winged Scoters
Based on the longer distance migration of the White-winged Scoter (breed from western Hudson Bay area through north western Canada into Alaska) they perhaps do leave earlier than the Black and Surf Scoters (3). Michelle notes that the Black Scoters appear ready to migrate. They are frequently seen flying up and down the Peaks Island backshore – hormones dictating an urge to fly. They typically leave New England for the North in early April.
Breeding Ranges of Surf, Black, and White-winged Scoters
Map from © Google with Modifications
Daisy and Valerie at Evergreen Landing witness a scuttle of activity.
The Red-breasted Mergansers are in full tilt – 3 males trying to impress one female. Heads whipping upwards and beaks opened, while scurrying along the water’s surface in a rather clumsy dance of who can knock the other down. And this dance has a name – “a salute-curtsy courtship display”. Typically three males will simultaneously 'court' a female. Once she chooses the most impressive male, she will chase the remaining two away.
Males Approaching the Female (Red Arrow)
Female Watches the Display
Female is Surrounded by Males
Female Watches as One Male (Blue Arrow) is 'Knocked Down'
Female Chases Away the Lack-luster Males
These mergansers are seasonally monogamous, forming pairs from February to end of March. We wonder which of the three males did she pick? Once the female selects her mate they migrate in pairs or small flocks. Are they currently in route to their breeding grounds in northern Maine, Canada Maritimes, Baffin Island, Greenland, or around Hudson Bay. They prefer tundra and northern boreal zone – near freshwater lakes or brackish wetlands. The female selects the nest location that usually involves some sort of shelter such as holes, crevices, or dense vegetation. The number of eggs ranges from 5-24. In some cases, as with other sea ducks, young from different nests may combine to form crèches accompanied by one or more females. (3)
There are dwindling numbers of Long-tailed Ducks, Common Goldeneyes, and Buffleheads along the shores of Peaks Island. Perhaps these species, too, are moving northward to their breeding areas.
The eastern population of Long-tailed Ducks has an extensive breeding range including all of the islands in the Canadian Arctic Archipelago, and Greenland (preferring coastal or tundra habitats). The eastern population of Common Goldeneyes mostly breed in Quebec, Labrador, and Newfoundland with fewer in Maine, Vermont, and northern New York. And finally, the cute little Buffleheads (eastern populations) breed primarily in southern Quebec. As cavity nesters, they prefer boreal forests. (3)
The Harlequin Duck (eastern population) breeds mostly coastal - on Quebec, New Brunswick, Newfoundland, Labrador, Baffin Island, a small section along eastern Hudson Bay, and southwestern Greenland. They prefer fast-flowing rivers and streams.
This sea duck story includes only a small fraction of the life histories of these birds – but it will hopefully tantalize your interest in viewing them along Peaks Island shores and perhaps spark an interest in further research. Thank you for your interest in reading this blog.
This Bird Blog is in Honor of Molly and Kristy.
1. Sibley, D.A. (2000). National Audubon Society: The Sibley Guide to Birds. Alfred A. Knopf, Inc. NY
2. Paruk, Dr. James. St. Joseph’s College. Pers. Communication.
3. Baldassarre, Guy. 2014. Ducks, Geese, and Swans of North America. Vol 2. John Hopkins University Press, Baltimore.
By: Patty Wainright
Reviewed by: Valerie Kelly, Sam Wainright, Michelle Brown, Marty, Michael LaCombe
Photos and Drawings: PW (unless otherwise noted)
Map: Color added to Google map
