I was in the parking lot of a bayside beach in Truro recently when I heard a sound I couldn’t place - a strange, high pitched wail drifting in from somewhere off toward the beach. It wasn’t something I’d ever heard before – like the noise from some unfamiliar construction machine working in the distance.
When I got out to the beach, I discovered the source – a massive raft of 1200 Black Scoters blanketed the surface of the bay just off the beach. I was hearing the collective sound of many hundreds of male scoters simultaneously offering their plaintive mating call.
Now try to imagine that sound times several hundred and you might get a sense of the eerie atmosphere on this deserted beach that cloudy early spring afternoon. As the name would imply, a male Black Scoter is jet black, except for a lightbulb-bright orange knob adorning the bill. His melancholy song is definitely in keeping with the gothic attire.
The researchers who know the species best have pronounced the Black Scoter “one of North America’s least known waterfowl” because of an apparent lack of interest from hunters and their remote breeding areas in northern Quebec and Alaska. Only a few nests have ever been found. Like their other scoter brethren – White-winged and Surf Scoters, they feed on invertebrates year round, focusing on mussels and other bivalve mollusks during the winter.
Of the three scoter species that winter on the Cape, the Black Scoter is usually the hardest to find. But during April and early May you can sometimes find dense flocks of these migrants on any of the water bodies surrounding the Cape. In the fall you can also find them on big inland lakes, where tight, nervous flocks are sometimes grounded by bad weather.
The ferry route from Hyannis to Nantucket is often the best way to see masses of scoters from late fall through spring, as long as, like me, you’re willing to be that binoculared weirdo out on the freezing cold deck for the whole ride. Two such birders counted 25,000 Black Scoters along with 10,000 Surf and 3000 White-winged Scoters on this ferry crossing in October of 2013.
Off of Sciasconset on Nantucket, Chappaquiddick on the Vineyard, and Corporation Beach in Dennis have also been good places to see big scoter flocks in the past. Aerial surveys in 2004 and 2005 counted many tens of thousands of scoters in Nantucket Sound. These numbers may seem high, but scoters seem downright rare compared with the aptly named Common Eider, which number in the hundreds of thousands just off Monomoy each winter.
Scoters aren’t the only seabirds on the move right now. Loons, grebes, eiders, and red-breasted mergansers are all starting to head back to their northern nesting grounds. So while you’re waiting for your orioles and hummingbirds to come back, don’t forget about the other migration happening just a little offshore. We might take it for granted sometimes, but very few people in the world have access to the spectacular seabird migrations that we can see in our own backyards here on the Cape. Throw in the fact that we can also see super rare whales from shore, and you might say that we’re pretty lucky in these parts.