Frost and termination dust are sure signs of the inevitable change in seasons. Another sign at my house is the abrupt silence. I live on a small lake with a pair of Pacific Loons, not far from the boundary of the Kenai National Wildlife Refuge. At the end of the season, three or four extra loons arrive on the lake and the ensuing nights are filled with whoops and wailing. I always feel a pang of sadness when the party ends and the loons depart for the winter.
Pacific Loons are one of three species of loon that can be seen on the Kenai Peninsula. Pacific loons are smaller than Common loons and have a grey head that shimmers when the lights hits it. The third species, the Red-throated loon, is less common and has a vibrant red throat patch.
Pacific loons are the most abundant loon in North America, although the Common loon may be better known due to their iconic, eerie call that is often used in movies. Pacific loons spend most of the year in ocean waters along the Pacific coast, but breed in lakes across Alaska and northern Canada.
Each spring, a Pacific loon pair takes up residence on my lake soon after the ice breaks. They gracefully stretch up their long necks and jump slightly as they dive into the water. They preen their white bellies and scratch their sides with their feet. They whoop and wail.
Pacific loons nest on the ground in simple depressions next to the pond edge. One or two eggs are laid. Both the female and male incubate the eggs. The parent that is not on the nest is usually around, tending to forage on the nest pond. The hatchlings are led away from the nest and cared for along the pond edge. Adults feed the young for about a month as the young learn to forage. The young loons begin by dipping their heads into the shallow pond edges to get insects and larvae and graduate to diving for fishes.
A researcher studying Pacific loons in northern Canada found that loons remained in their nest pond even after their nests had failed instead of moving to more productive ocean waters. “Roving” flocks of loons also visited the ponds with unsuccessful nests, while avoiding the ponds with chicks or eggs. Often, the visiting flock would be met with territorial displays. These behaviors caused the researcher to hypothesize that territories were scouted and claimed in the fall so that real estate shopping would not take up too much of the short nesting season in the next year.
The small groups of loons that congregate on my lake at the end of the season never struck me as confrontational. They swim lazy circles together and call back and forth. Other researchers have noted that Pacific loons become more social as the end of summer nears and staging occurs in small flocks, in preparation for migration. In the winter and during migration, Pacific loons can be downright gregarious and congregate in large flocks of over a thousand individuals. I think about where the loons that nest on my lake are now and where they are headed while I pull my snowshoes out of storage.
Dr. Dawn Robin Magness is a landscape ecologist/GIS manager at the Kenai National Wildlife Refuge. You can find more information about the Refuge at http://kenai.fws.gov or http://www.facebook.com/kenainationalwildliferefuge.