– Written by Logan Parker, MLRC Community Engagement Coordinator
– Photographs courtesy of Margaret Viens
Manning the front desk of the MLRC means answering a lot of varied questions relating to the Belgrade Lakes Watershed. “How’s the water quality of Great Pond? -Where is the best place to hike with my kids? -How’s the fight against milfoil? -The neighbors said you had a public restroom. Can I use it?” Among the most common of questions, however, relates to one of the watershed’s most popular residents: “Where do the loons go in winter?”
If there were a mascot for our continent’s Northern lakes, the Common Loon (Gavia immer) would surely fit the bill. A large bird with striking black and white breeding plumage that produces some of the most enchanting of vocalizations of the avian world, its no surprise the loon has so many admirers. Each summer loon-enthusiasts observe loons drifting along the lake surface, peering and diving for fish, and rearing their fluffy, precocial young. Yet to many, the fate of our resident loons after ice-in is shrouded in mystery.
I was once asked if our loons plunged to the lake’s depths and buried themselves in the sludgy benthos as a means of surviving the winter. Strange as it sounds, this strategy for winter survival is not unheard of in our lakes – indeed, many native reptiles and amphibians employ this strategy each year. Unlike Snapping turtles and Green frogs, however, loons lack the ability to diffuse oxygen directly from the water through their skin – a process known as cutaneous gas exchange (Heinrich, 2009). Instead, loons take part in seasonal movements known as migration.
To say that loons migrate away from the Belgrade Lakes for winter might be a satisfactory answer for some, but if you are anything like me, that answer simply raises more questions about our wintering loons. “Where do they go, why do they go, and what is life like for these loons?” are some of the first questions that pop into my mind. As many of us fall residents know, each fall our resident loons move out: adult loons departing first followed by the flocks of younger loons heading out a few weeks behind (Klein, 1990).
Unlike their fellow summer residents the wood-warblers (many of whom migrate as far as Central and South America each winter) our loons may not be traveling far. In the case of the Common loon, the where they go has much to do with the why they go. The loons follow their gut, or more accurately, they follow that which will fill their gut: fish. Fortunately for the loons of the Belgrade Lakes, a bounty of fish is available year-round just 50 miles to the south in the Atlantic Ocean. It difficult to know whether our loons are among those seen diving for fish off Maine’s coasts each winter – it’s possible that they move further south along the Eastern seaboard. Regardless, our state’s coastal waters teem with Common loons (alongside Red-throated loons which have travelled all the way from the arctic ocean) each winter.
The life of a Common loon living on coastal waters is markedly different from the relative sereneness that is a summer spent on our lakes. Yet some aspects of life remain the same. Loons will continue to dive for their aquatic prey, but must also remain wary of eagles that will continue to predate upon any bird that drops its guard. Loons abandon elaborate breeding plumage for a more drab palate of colors. Wintering loons are muted not only in plumage, but in vocalization as well. Though they still defend individual feeding territories by day, the nighttime gregariousness birds means fewer evenings filled with their haunting calls (Stokes, 1989).
Want a glimmer of summer in the midst of the winter cold? Consider taking a day trip to the Maine coast to visit loons as the adult birds prepare for another summer of life on our inland waters. The younger loons will adjust to a life on the seas, but after reaching breeding maturity, they too will make their way towards less salty waters (USGS, 2015).
For some FAQs on Common loon migration, visit here.
Heinrich, Bernd. Winter World: The Ingenuity of Animal Survival. New York, NY: Ecco, 2009.
Klein, Tom. Loon Magic. Ashland, WI: Paper Birch, 1989.
“Loon Study – Frequently Asked Questions.” Common Loon Migration Study. U.S. Geological Survey, 3 Nov. 2015. Web. 19 Nov. 2015.
Stokes, Donald, and Lillian Stokes. Bird Behavior. 1st ed. Vol. 3. Boston: Little, Brown, 1989.