Saturday is the winter solstice. As most Alaskans know, this is when the sun reaches its lowest point on the horizon with zero hours of daylight north of the Arctic Circle. This is also when the sun is directly over the Tropic of Capricorn, making it the longest day of the year in the southern hemisphere. While maybe just a lesson in geography for some of us, many of our long-distance migratory birds are very aware that their summer days are getting shorter while ours are getting longer.
Consider the Olive-sided Flycatcher, a common breeder in mature mixed deciduous-conifer forests, such as found along the Swanson River Road in the Kenai National Wildlife Refuge. Even as we sip our coffee at Kaladi’s or some other local cafe, our flycatchers are likely chasing aerial insects in shade-grown coffee plantations in the Andes Mountains, a beneficiary of ecologically-minded human consumers. If you’re so inclined, look up “bird-friendly” coffee certification by the Smithsonian Migratory Bird Center.
Our Yellow-rumped Warblers, one of the most common breeding forest birds on the Kenai Peninsula, may well be hanging out near prime beach front on the East Coast. While studying American black ducks wintering at Chincoteague National Wildlife Refuge, I frequently saw this songbird — once called the “Myrtle warbler” — foraging in wax myrtle, an evergreen shrub related to myrica gale that grows along wetland edges in the Kenai Lowlands. Wax myrtle grows along the Atlantic and Gulf coast from New Jersey southwards.
Townsend’s Warblers, another wood-warbler species, are abundant breeders in the mature white spruce around Fuller Lakes. Local populations were likely hit hard by the 15-year spruce bark beetle outbreak that killed 1 million acres of mature spruce on the Kenai. This time of year, these warblers not only change location from Alaska to California and the highlands of Mexico and Central America, but they change their diet from insects to honeydew excreted from sap-sucking insects, plant galls and a few seeds.
Red-necked Phalaropes, a shorebird that commonly nests in wetlands adjacent to lakes such as the far side of Engineer Lake, are literally scattered wherever there are oceans this time of year, but primarily off the coasts of southern South American and Africa. Imagine a small shorebird that bobs on the ocean’s surface during winter, feeding on krill, copepods and amphipods. Phalaropes sometimes associate with other animals, such as Gray Whales and Oldsquaw Ducks, which apparently stir up food from the bottom while feeding. Phalaropes have even been seen gleaning parasites from the backs of whales!
The Lesser Yellowlegs is a more typical shorebird, a common breeder in forested wetlands on the Refuge. Stable isotope analysis of primary feathers conducted by Sadie Ulman, a graduate student from the University of Delaware, confirmed that Lesser Yellowlegs captured on Chickaloon Flats likely migrated from South America, quite possibly around Lake Titicaca on the Peruvian-Bolivian border. Imagine our yellowlegs — fledging from the muddy seashores of Turnagain Arm — now wintering on the largest South American lake at 12,000 feet in the Andes. “Wintering” is used loosely in this context as 13 hours of sun bombards Lake Titicaca even as we go about our daily business in 6 hours of winter twilight.
Arctic and Aleutian Terns nest in a small mixed colony on Headquarters Lake. They are very similar in appearance so the less-than-avid-birder might not appreciate that these really are very different species. Arctic Terns are the champion of long-distance migrants, seeing two summers each year as it migrates from its northern breeding grounds including the Kenai Peninsula along a winding route to Antarctica and back, a round trip of over 44 thousand miles! In contrast, Aleutian Terns until recently were thought to winter and breed in and on both sides of its namesake, the Aleutian Islands. However, observations of Aleutian Terns near Hong Kong, Singapore and the nearby Indonesian Island of Bintan in the South China Sea indicate that some birds migrate through, or winter, in these areas.
Even as the nomadic and exotic lifestyles of these migrants allow them to spend longer and warmer days in places far south of the Kenai Peninsula, consider that we have a few birds that have chosen (in an evolutionary sense) to survive here during the dark and cold of winter with appropriate adaptations. Ravens are black to absorb sunlight, ptarmigan grow feathered “snowshoes” on their toes, Steller’s and Gray Jays cache food, Boreal Chickadees drop their nocturnal body temperatures 20 degrees, and American Dippers grow down between their feather tracts like waterfowl.
Frankly, birds are cool. It’s hard not to appreciate their lifestyle choices even as many of us sit tight during the winter months while others fly south as “snowbirds.” I’m just glad that the winter solstice is almost behind us.
John Morton is the supervisory biologist at Kenai National Wildlife Refuge. You can find more information about the refuge at http://kenai.fws.gov or http://www.facebook.com/kenainationalwildliferefuge.