bird on, ryan

-A smaller swallow

-More “fluttery” in flight than the nearby TRES and Barn Swallows (BASW?)

Ry

Yeah, swallow ID is often a difficult process, particularly if one is viewing birds under poor conditions, which with swallows can be more frequent than other birds due to their foraging methods which can often place them in harsh lighting causing strong washouts of color, or in extremely backlit situations with little color being viewable (e.g. Cave Swallow in NY on a overcast day). All of this, like you said, results in the usage of color being a good first step in identifying species, but not always useful. So what do we use?

Flight patterns for me, and many birders that I have been around is extremely important, as is tail shape (think Barn Vs Tree). Recent discussions with Rich Stallcup over separation of Tachycineta swallows (Tree, Violet-green), and Hirundo swallows (particularly Cliff and Cave), led Rich to give his “observations” on swallow ID, and one of the main features he used in both sets of swallows was the opaqueness of the wings strongly backlit, and how “twinkly” the birds appeared flapping. Now, he is without a doubt a very astute observer and takes with him many, many years of combined knowledge to reach these conclusions, but it is obvious that more should go into swallow ID than just color or silhouette.

As far as the separation of Northern Rough-winged Swallows (NRWS) and Tree Swallows (TRES) is concerned, there is an obvious size difference (0.5 inch) and flight style difference, but the overall color is a major indication that I go for (if I can get a good look at it). I feel that Tree Swallows in any plumage live up to their species name (T. bicolor), and show a strong difference of brown and white. For Rough-wings I feel that the brown is separated from the white, however there is a blending effect on the chin and upper breast with a diffuse gray-brown that appears as if an artist smudged pencil from the birds back onto the white of its breast.

Once again, I have more observations on this and would like to add more to it, but perhaps a combined effort for an article, or a series of articles, would be best for these thoughts; something along the lines of Kenn Kaufman’s articles in Birder’s World for separation of ‘look-alike’ species. Let me know, and I’ll consider it more (on top of all the other articles I have brewing).

Until next time,

Chad

PS Another great ID aid when viewing swallows is of course their calls. I often have a hard time remembering them from season to season, yet with a little bit of exposure I regain this knowledge, and as I walk in the field I often can know the swallow flocks foraging above me even without looking.