At Tigertail Beach yesterday morning we sighted and were able to photograph numerous shorebirds. Among these shorebirds were many Dowitchers. Short-billed and Long-billed Dowitchers often mix with each other and forage together. The two species of Dowitchers are very difficult to differentiate from each other, but as luck would have it, I was able to photograph the two species side-by-side, both in nonbreeding plumage.
We have identified the Dowitcher on the left as a Short-billed Dowitcher and the one in the middle as a Long-billed Dowitcher. We were able to differentiate the two species as follows:
- You can see in the photo that the Dowitcher on the left has a bill considerably shorter than the other one. The bill sizes of the two species do overlap, particularly since the female generally has a longer bill than the male of the same species. However at the extremes there is definitely a difference: the bird on the left is probably a male Short-billed Dowitcher and the one in the middle, a female Long-billed Dowitcher.
- The bill of the Short-billed Dowitcher has a a slight downward curve, while the bill of the Long-billed Dowitcher is straight. You can see this in the photo.
- The Short-billed Dowitcher's eyes are at a higher angle above the bill (loral angle) than the Long-billed Dowitcher's eyes. This is obvious in the photo.
The Long-billed Dowitcher is already on our Life List, but the Short-billed Dowitcher is a new species to the list, which now stands at 239.
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