Swans, yes, but which ones?

Posted April 8th, 2013 by kcorliss. Comment (0).

First, dear reader, notice the snow-and-ice background. Indeed this area of the Upper Midwest continues to be held tightly within the grip of a cold and damp cycle. Here in Fargo I hear the high temperature for the year has been…drum roll…43 degrees. Hardly a late winter/early spring to brag about. If someone has access to that pixie dust known as global warming, could you back that truck up and dump a load of it here. Please?!

To the subject at hand…this photo comes to me via Bob E., a friend and fellow aviator with an eye toward birds, taken at his lake place in western Minnesota last Friday. Even the most casual of observers would surmise that what we are looking at here is a pair of swans (Cynus sp.). The more-than-casual observer wants to know, however, which swan? Would anyone like to take a guess at this one? Some hints and a little background might help in your efforts at identifying these birds to species.

Historically, trumpeter swans (C. buccinator) nested in this area but were reduced in population over the decades to the point where the birds were labeled “threatened” in Minnesota. It is highly susceptible to lead poisoning (ingesting shotgun pellets while feeding). An aggressive reintroduction program started many years ago has met with tremendous success and the birds are proliferating across a lot of Minnesota. Sightings outside of their usual range (i.e. North Dakota) are increasing every year even to the point where North Dakota now even has a confirmed nesting attempt.

On the other hand, tundra swan (C. columbianus) populations have not really been threatened. This is the species which nests in the High Arctic and in Alaska and migrates through our area–sometimes in huge numbers–twice a year, going to and from wintering grounds in Chesapeake Bay (at least “our” population does). Seeing this species is a usual occurrence this time of year. In fact I saw a pair on the edge of town yesterday.

It’s safe to say these birds are one or the other, but which one is it? Care to venture a guess? There are no penalties for wrong answers by the way.

Oh, in 2006 the venerable David Sibley was kind enough to impart upon the uninformed masses his take on the separation of these two species. It’s exceptionally good, well worth your time, and accessible here. Good luck.

 

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