First off, we’ve had a comment thread running on our most recent post on the pelican die-off in North Carolina. Click here to read biologist Sara Schweitzer’s most recent input.
Now, for today’s content. For a month or so now, we’ve begun seeing scattered reports of loons turning up dead and alive on and near SEANET beaches. This is a normal phenomenon at this time of year. Two species occur here on the East Coast with some regularity: the Common and the Red-throated Loons. Common Loons in particular are generally associated with northern lakes from here in New England on up. Red-throated Loons push the envelope, breeding in northern Canada, well into the Arctic circle on tundra lakes. But when summer ends, both species have to move on and find open water. They range up and down the Atlantic coast in winter, and generally stay close to shore, making them readily visible to bird watchers on the beach.
Loons are extremely awkward and vulnerable when on land, so aside from the breeding season, a healthy loon will not be found hauled out on shore. That’s why a find like Dick Jordan’s, a Common Loon sitting on the sand in Wellfleet, MA last month, qualifies as a beached bird by our standards. Loons may haul out for many reasons–starvation, oiling, and disease can all leave the birds unable to contend with the cold and rough ocean waters. Once they haul out though, they are easy prey for predators, and also begin to suffer from conditions like pressure sores on their breasts. And of course, they cannot feed once on shore.
Loons are hardy indeed though, as a photo sent by Helen Rasmussen in Maine demonstrates. This Common Loon was spotted a little ways offshore, and Helen noticed that the bird’s lower bill was considerably shorter than the upper. She raised the possibility that this is a congenital deformity, much like those seen with increasing frequency in forest birds in Alaska and the Pacific Northwest. Without a closer look at the beak, it’s tough to say whether or not the bird was hatched that way. If not, the other possibility is that this bird’s truncated beak is a result of a traumatic event.
Helen’s bird seemed to be doing ok, outwardly, though its ultimate fate is unknown. Your SEANET blogger can speak from personal experience that loons can live with broken beaks at least for a while: I fish on the lakes of Maine every year, and a couple of years ago, I observed a loon with its upper beak snapped off successfully fishing. Of course, a broken beak is a significant handicap, and when prey is scarce, it could easily become a fatal one.
As to how loons could sustain such trauma, speculation certainly enters in prominently here, but one thing is for sure–Common Loons engage in violent combat with each other, and their beaks are their main weapons. The potential is there, then, for the beaks to be damaged in such fights. I have occasionally seen birds that have crash landed on pavement suffer beak trauma as well. There is no way to know for sure, but one thing is certain, these birds are tough!