Eiders we’ve known

6 08 2014

Seanetters don’t find all that many banded dead birds, and probably the most common species to be found banded is the Common Eider. Of course, this is one of our top beached birds overall, so the odds are higher than for many species our walkers find only rarely. But not every species is being actively banded. Eiders are, and by following up on these bands, we get a sense of where those banding activities are going on.

Warren Mumford, walking in Chatham on Cape Cod, found a banded female in April. Here is the bird, and the certificate giving the information on her:

Found in Chatham, MA in April. (photo by W. Mumford)

Found in Chatham, MA in April. (photo by W. Mumford)



We’ve been interested in the wintering eider work going on in Rhode Island, including satellite tracking of individual birds by researchers at URI, so we are most pleased to contribute some low-tech data in the form of a banded bird report.

Advanced decomposition in  this banded eider. (photo by H. Rasmussen)

Advanced decomposition in this banded eider. (photo by H. Rasmussen)

Farther north, Brad Allen works with eiders on their breeding islands, and when I saw that Helen Rasmussen, who walks for us in Portland, Maine, had found a banded eider in July, I was fairly certain it would have been one of Brad’s. Sure enough, the certificate indicated that the bird was banded on Ram Island (or thereabouts) in mid May, when the birds are nesting. Ram Island is just off of Portland, so Helen’s bird was a local and appeared to have been dead for some time. It leaves one to wonder whether she was able to successfully rear her young before she died.

As I was putting this post together, I found a report on a project of Brad’s on Flag Island in Maine studying the eider population there. I am particularly interested in much of this paper as it covers some of the dynamics between eider ducklings and the Great Black-backed Gulls who eat them. As someone with great personal and professional affinities for both these species, their conflicts are of keen interest.

As the paper points out, the newly hatched ducklings mass together in groups called creches, with young from multiple mothers all traveling together under parental protection. The paper notes that the ducklings enter the water within hours after hatching, and, on Flag Island at least, leave the shores of their place of hatch and are lead off by their mothers to presumably safer waters. It is possible then that Helen’s bird did have young she was still supervising near the shores of Portland when she met her unfortunate end. What happened to any ducklings she may have had with her is unknown.

That brings me to the final eider of the day. Or at least, I believe it to be an eider. It’s a headless, fluffy duckling with eider-looking feet. Mary Dwyer, who walks Seapoint Beach in southernmost Maine, found this bird on July 9th.

Headless seaduck chick. (Photo by M. Dwyer)

Headless seaduck chick. (Photo by M. Dwyer)

It’s quite rare that we find carcasses of such young birds, so I have little experience with their i.d. But in my internet searches, “Common Eider chick” turned up similar looking birds to this specimen. I also tried looking up “scoter chick” just by way of comparison, but google assumed I meant “skater chick” and showed me altogether less useful images.

That wraps up my last post until I return from my summer hiatus. I will be vacationing along a lake in the middle of Maine, and preparing to teach chemistry to eager minds come fall. Enjoy the remains of the summer, my dear readers, and I will you see you here upon my return.