Selasa, 23 Juni 2009

Mystery Duck in ND: The Final Chapter

Our mystery duck preening.

We finally re-found the weird-looking scaup on an adjoining part of the lake where we'd originally spotted it. And this time the light was a bit better, so we took good long looks in between getting more still and video images. Blowing up one of the digiscoped stills on my camera screen, I noticed something odd. The scaup was preening and this gave me a unique angle on the bill and the bight orange-red color patch.

So I blew it up more...


and more still.

"Hey! That's some sort of colored tag attached to the bird's bill! It's NOT a natural part of the duck."

This view showed a clear gap between the bill and the colored patch, leading us to suspect this was something artificial.

From a normal angle, with the scaup swimming in profile, the colored patch looked more like a part of the bill.
But there were still things that bothered us about this bird. It looked and acted differently than its fellow male lesser scaup nearby. This made us wonder if the bill marker/tag was affecting the bird in some way. Was it affecting his social status among the other scaup? I've seen albino birds attacked and driven off by members of their own species. Was it physically painful or did it affect the bird in some physical way? He certainly looked duller and less round-headed and acted shyer than his peers most of the time we watched him.

Here's a video I shot through my scope that shows the marked scaup's behavior while apparently trying to defend a female (his mate?) from other potential suitors. NOTE: You might want to turn down your speaker volume: the wind noise on this video is loud.




That evening at the social hour, I cornered Ron Martin, one of North Dakota's top birders, to ask about the bird.

"Oh yeah, we've seen a few scaup like that over the years. There's some guy doing research on them. You can probably find him on the Internet."

Well, Ron was right. Searching "ducks with bill tags" I got a posting from MOU-net. It gave a number for the Minnesota DNR where, back in 2005, birders and hunters were encouraged to report sightings of tagged birds. The kind souls at MN DNR were no longer collecting the sightings, but they pointed me to a professor at Louisiana State University who, apparently, had lead the research projects that were tagging scaup. I sent off an e-mail asking if he wanted my report but have heard nothing yet.

Scaup are experiencing a fairly rapid decline in population and waterfowl researchers are trying to discover why. Lesser scaup migrating up the Mississippi River were being bill tagged back in 2004 and 2005. If I hear anything from the researchers, I'll let you all know.

I was disappointed that this was not some weird vagrant duck, though I knew the chances of that were slimmer than a male pintail's tail. I was, however, glad to have solved the mystery. I feel a bit of pity for the poor duck, which has had to live with that crazy thing attached to its bill. If nothing else, I hope the researchers eventually discover what's behind the scaup population decline.

Thanks for bearing with me as I told this story. It was too much for a single post. Thanks to everyone who commented, especially Paul Roisen from Iowa, who sent me this photograph of a strikingly similar species from South America, the rosy-billed pochard:
Rosy-billed pochards from South America.


Artificially-rosy-billed lesser scaup from North Dakota.