In this post I am going to discuss a few fieldmarks for separating the two dowitcher species from each other. I will start with adults in alternate plumage and then discuss juveniles. The two species are extremely similar in basic plumage and given the rarity of Short-billed Dowitcher in the county in winter, I am not going to discuss the slight differences in detail. You should always try to confirm a winter Short-billed Dowitcher by call. To reduce the learning curve, I will be covering a subset of the available fieldmarks and focusing on ones I find especially useful or easy to use. Alternate Plumage When first viewing an adult dowitcher in alternate plumage, I start by assessing the overall tone of the reddish underparts and how extensive this coloration is on the underparts. In Long-billed the underparts tend to be more brick-red and this color extends all the way through the vent. Short-billed, on the other hand, has more orange-toned underparts and this coloration ex...
Dowitchers occur in three distinct plumages – alternate (breeding), basic (winter or non-breeding) and juvenile (young of the year). Being able to determine the plumage of a particular dowitcher is essential as plumage features that apply to a juvenile, for example, may not be relevant for an adult. Dowitchers change between plumages by going through a molt. Molt is a process that takes some time and it should therefore come as no surprise that birds on migration are often in active molt from one plumage to another. Since these transitional plumages resulting from active molt can cause identification pitfalls, I will also give some examples of them and how to recognize them. The photographs on this post and the next were kindly provided by Peter Schneekloth (PS), Brad Hacker (BH) and Lynn Scarlett (LS). Basic Plumage Dowitchers can be in in basic plumage starting from as early as August through to April/May. Note that young birds may retain basic plumage through the ...