Saturday, April 5, 2014

Ring-necked Duck vs. Scaup

In a recent post I showed a rather indistinct photo of what we concluded was a ring-necked duck (or two). Here is a better shot I got yesterday that provides a nice comparison between the ring-necked duck and a scaup, which appear quite similar at a glance, with dark heads, breasts, and tails, lighter flanks, and bluish/grayish bills.

The duck in the foreground is the ring-necked duck. According to Sibley (Field Guide to Eastern Birds, 2003), the black back and the white "spur" on the side (just behind the base of the neck) are distinctive, as is the white outline on the bill. As I mentioned in the earlier post, the sharp angle to the head is also diagnostic. As Sibley puts it, this duck is "best identified by tall head with sharp peak on rear crown." (The white marking on the bill also tempts one to call this a "ring-billed" duck -- a good sign that actually it is a ring-necked duck. Go figure.)

The duck to the rear is a scaup. It lacks the field marks of the ring-necked duck that I noted above, and has white flanks and a gray back, in contrast to the ring-necked duck's gray flanks and black back. The greater and lesser scaup are very similar. I'm guessing this is a lesser scaup, based on the fairly tall head, which is the main way of distinguishing it from the greater scaup, which has a larger, more rounded head. However, from this angle it's difficult to say for sure. The lesser scaup is also the more likely species to be found here, as they winter all across the southern tier of the U.S. as well as on the coasts, while the greater scaup is said to prefer salt water and winters mainly on the coasts, as well as some smaller inland areas in the south, from eastern Texas through Arkansas. See the comparative range maps: lesser scaup vs. greater scaup. This is also borne out in Minnesota eBird records for the two: lesser scaup vs. greater scaup.

Today we saw our first northern shovelers of the season (boldly colored ducks with enormous bills), and a belted kingfisher. I am keeping a 2014 bird list (also available from the page links at the top of the blog). We've often kept records of what we've seen, but this is the first time in a while we've started a numbered list early in the season, and I'm hoping to keep it going throughout the year. We're up to 34 species so far, and with spring migration really getting started, that should keep going up pretty steadily.

Happy birding!

1 comment:

Anonymous said...

This was a very helpful description! I had ring-necked and scaups all mixed together in one photo and I was having trouble figuring them out! Thank you!