The Upper Midwest remains — for the moment — in winter’s clutches. This fact is oddly comforting to me, stuck as I am in the pleasant but seasonless climate of southern California. In one sense, I dread the coming of spring in Wisconsin and Minnesota. Each year I find myself weeks behind schedule. While my study animals in the Upper Midwest spend April facing real problems like migrating safely, settling on their territories, contending with hopeful usurpers, and beginning their breeding effort, my Aprils are more mundane. I prepare study guides, conduct review sessions, and quiz my students about evolution and ecology in preparation for the final exam.
Despite the bland Mediterranean climate and muted seasonality of southern California, I am not entirely in the dark about the coming of spring. When I hear house finches, orange-crowned warblers, and the impossibly loud and bubbly song of the tiny house wren out my front door, I understand that loons are on the move. Last Wednesday’s birdwatching trip to the Newport Pier provided the most stark reminder yet. As I stood next to my spotting scope, scanning the ocean for pelagic rarities like jaegers and shearwaters, a familiar dark silhouette appeared several hundred yards offshore.
His crisp breeding plumage gave him away. But just to drive home the point, this adult-plumaged Common Loon uttered several awkward, truncated yodels — to the befuddlement of many Western Grebes rafting nearby. No doubt this male will improve upon his sputtering vocal performance by the time he reaches his breeding territory in British Columbia or Alaska. For the time being, his voice reminded me that I have much work to do in the coming weeks.
My tardiness reaching the Upper Midwest each year guarantees that I spend the first two weeks of every field season in a tizzy. I race frantically to a boat landing, drop my canoe into a lake, and make a beeline for the breeding pair. After ID’ing them from their leg bands, I throw the canoe back up on my roof rack, drive to the next lake, and repeat the process. It is not the way one might choose to take in the wonders of early spring!
But enough of my problems. Loons are the ones most impacted by late spring thaws. As Linda Grenzer’s above photo from northern Wisconsin shows, lakes are only beginning to open up in the Northwoods. This means that, for now, breeding loons must be content feeding and resting on rivers and dodging ice floes, like the bird below from Linda’s video:
Perhaps today’s warmth will melt enough ice for breeding pairs to begin to land and stake out their territories for the year. They must rue each day that passes before settlement. A recent statistical analysis showed that each four days that pass before loons can take possession of their territories pushes back nesting one day. On the one hand, this is good news, because it means that breeders bounce back from late ice-outs by being more thoroughly recovered from migration and ready to nest when they finally do settle. On the other hand, like me, they must be pretty anxious to get their summer’s toil under way.