Date: Fri, 23 Nov 2001 17:23:19 EST Reply-To: Maryland Birds & Birding Sender: Maryland Birds & Birding From: Paul O'Brien Subject: Possible Slate-colored Fox Sparrow at Rachel Carson MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit This morning (11/23) from about 10AM to noon, Michael O'Brien, Louise Zemaitis, Gary Rosenberg and I birded the "b" area of Rachel Carson Conservation Park off Zion Road in Montgomery Co. (see page 87 of the new Birder's Guide to Mont. Co.). We entered a well defined trail toward the east that began almost as far south of the one-lane bridge as the bridge is from the parking area. As we climed the first rise in the trail (just a few feet off the road) a Fox Sparrow jumped up to a perch about 8 feet off the ground to our right. It had a flat gray head, nape and auriculars that contrasted markedly with strongly rufous wings and tail. The malar streak was nearly black, but the spotting on the sides exhibited increasing rufous tones from the shoulder to the flanks. I could not see the mantle. The bill was unremarkable, i.e., it was probably not a Thick-billed Fox Sparrow. The bird most closely resembled the upper figure on page 513 of Zink and Kessen's article in Birding vol. 31 #6 (Dec. 1999) pp. 508-517, "Species Limits in the Fox Sparrow", and example "J" in the lower left corned of David Beadle's plate on P 514 of the same article. Beadle's plate also appears as Plate 15 of James Rising's book "The Sparrows of the United States and Canada". There the bird in question is labeled "40c". My best guess is that the Fox Sparrow we saw was Passerella iliaca schistacea, the subspecies that inhabits the Rockies from Colorado to Alberta and west through Idaho to Oregon. Red Fox Sparrows, the iliaca group, show rusty auriculars. Sooty Fox Sparrows, the unalaschensis group, are very dark, without contrasting gray heads. Thick-billed Fox Sparrows, the megarhyncha group, have, well, big thick bills. In the Slate-colored Fox Sparrow (schistacea) group the altivagans subspecies tends to show warmer rufous tones in the nape and auriculars and hence lacks the obvious contrast between the gray head and nape and the rufous wings of schistacea. Gary tried to "digiscope" the sparrow, but it dropped out of sight before he could set up. If anybody goes out that way in the next few days, please try to get a look or a photo. Although these are just subspecies at present, Zink has proposed splitting them, and DNA evidence seems to support four identifiable groups. There is therefore a possibilty that schisticea could someday be declared a species. Even if it is not, it is worthwhile documenting such extralimital wanderings just to enlarge our understanding of bird movements. Paul O'Brien Rockville, Mont. Co., MD pobrien776@aol.com 301-424-6491 ======================================================================= To leave the MDOsprey list, send e-mail to listserv@home.ease.lsoft.com with the following message in line 1: signoff mdosprey ======================================================================= =========================================================================