Those late summer “Dodgy Dows”

Dowitcher, Boulmer, Northumberland, July 2017 (Alan Curry) Present for several days this worn adult (or 2nd cal yr?) showed well on a tidal beach in the UK. Certain aspects of the bird caused locals to consider Short-billed.

My old buddy Alan Curry, from the UK, sent me a pic of this dowitcher that was present in north-east England in mid-July. Long-billeds are vagrants and the more likely suspect, but with a couple of records of Short-billed, any dowitcher must be examined carefully. Assumed to be Long-billed, he had some concerns about the habitat choice (rocky, tidal seashore, rather than inland freshwater), plumage and the obvious fact that this bird has a short bill.

Worn breeding plumage dowitchers are difficult and tricky here in the eastern US. I told him it is not a problem exclusive to the UK. He asked for my opinion on the UK bird to make him sleep a little easier!

Indeed this month a few birds have shown up that people have had trouble with so I figured I’d throw a few comments together to illustrate what I personally look for. The issue is compounded here in the US by the presence of the inland, ‘prairie’ race hendersonii, which migrates along the eastern seaboard in good numbers and is brighter than the Atlantic form griseus, and is slightly larger and more colorful and often hard to separate from Long-billed.

Back to the UK bird? I won’t go into a long treatise of these birds, there are plenty of papers and resources on the web, so this will just be a few things I hone in on. Despite the short bill, I think this is a male Long-billed for the following reasons:

  • First, the underpart color is extensive, reaching underneath the legs. It isn’t as “brick-red” in saturation as many Long-billed’s, but color is variable (especially when represented in photos).
  • The upperparts are quite dark, especially the mantle.
  • A slight neck collar formed by a coalescing of barring/streaks.
  • The internal bars to the scapulars are bright, rufousy colored.
  • The barring at the carpal area is distinctly chevron-shaped, not lozenge/spot-like.
  • The tips to some of the upperparts are white-tipped (similar to tertial  tips of a White-winged Crossbill).

Jizz is hard from this one shot, but it looks like it could well look very rotund/dumpy, but it is hard to judge. Judging bill length, shape and loral angles to me are less important than the features i can see noted above, so find them often misleading or a red-herring. Habitat choice is also misleading since Long-billed can be found in habitat similar to Short-billed (as in this case).

Long-billeds also moult inner primaries earlier than griseus Short-billeds since they are shorter distance migrants, but this bird was fully-winged and any molt clues are likely better off used later in the summer (late August?).

I remember looking hard at dowitchers in Cape May during my years there, trying to separate some hendersonii Short-billed from Long-billed was sometimes a bit of a headache for A UK birder that didn’t grow up seeing them regularly.

Comparison sketch of Long-billed vs Short-billed noting some subtle differences, Cape May, August 1991, Chevron-shaped markings with a paler terminal fringe (if unworn) at the carpal area is the first thing I gauge on difficult birds.

The chance to see Long-billed with both races of Short-billed was key, and even then, some birds can still be tough if not seen well, or heard to call. I still struggle with some individuals.

Ad Long-billed (left) and hendersonii Short-billed (right), Cape May Meadows, August 1991. Note the rotund shape and “greyer-faced” look of the Long-billed. The breast side barring is almost worn off on the Long-billed. The brighter, golden fringes to the upperparts, mantle and tertials are typical of hendersonii.

Flock of Short-billed Dowitchers, Connecticut (Nick Bonomo). This nice shot comprises what appears to be mostly hendersonii (H) and a griseus (G) and one bird that both of us are unsure about (?).

So, just a couple of comments to concentrate and dwell on if you happen to come across a silent, bright dowitcher in July/August.

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