Monday, September 17, 2012

Long-billed Dowitchers

If you attended our third shorebird seminar you would have heard quite a bit about picking out the Long-billed Dowitcher from the Short-billed Dowitcher. Keith Mueller has generously allowed the Audubon Alliance for Coastal Waterbirds to use his photos, and here is a striking shot one a Long-billed Dowitcher.

That is a Short-billed Dowitcher in the foreground. Even in this photo you should be able to pick out some of the features that distinguish one from the other. I wanted to also post a photo that Sean Graesser had used in his presentation that was taken by Patrick Comins as it can perfectly illustrate some of the differences.

No, Patrick did not stage this or edit the photo - these two birds are sitting on the dock at the Stratford marina. Can you tell which bird is which in the above photo? Yes, in this instance it really is that easy, and the bird with the longer bill and slightly straighter on the right is the Long-billed Dowitcher while the bird on the left is the Short-billed Dowitcher. However, we all know birding and surveying is not as easy as staring at a frozen moment in time with two birds perfectly posed for you at a very close distance while they conveniently hold their heads in the same direction.

You can also notice that, at this point in the season, these Long-billed Dowitchers have a more gray and drab appearance with less of the buffy colors the Short-billeds do. The feather edges feature more golden on the Short-billed and brown on the Long-billed. The Short-billed has a steeper forehead with a more arched supercilium as opposed to the flatter, for both features, Long-billed. Body shape is a very good feature for these species, as the Long-billed appears to me to often have a longer and deeper back and thus a longer tail and rear, with the Short-billed having a flatter back and more stout rear. Many people say the Long-billed has a "humpback" appearance and it looks like it swallowed a grapefruit (being very rounded) as opposed to the more relaxed and natural curves of a Short-billed.

These are just some of the likely identification points for a tricky couple of species that will inevitably confuse even the best of us in the field on many occasions. Individual birds can vary a great deal, and when you have two such similar species and some may appear much like the other species even when they are not. It is best to use a wide array of features to really hone on in picking out the much more rare Long-billed Dowitchers from the many Short-billed Dowitchers you will see in Connecticut.

Audubon Alliance for Coastal Waterbirds, Audubon Connecticut and the Connecticut Audubon Society partnering to improve conditions for coastal waterbirds in Connecticut.

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