Vermont Rare Bird Reports 2021

Also seen by a beginning birder named Jenn, last name and email not known to me, who recently moved to Vermont. I pointed out the bird to her.

Low overcast/lake fog, light NW wind, ~57 degrees F

Nikon Monarch5 8x42 binoculars

Acquainted with Nelson's Sparrow (Interior), A. n. nelsoni, from previous observations in the U.S. Midwest and in Vermont. Acquainted with Nelson's Sparrow (Atlantic Coast), A. n. subvirgatus, from observations in Maine. Acquainted with Saltmarsh Sparrow (A. caudacuta) from observations in Maine.

Low vegetation between mudflats and a stand of small willows. Other birds in the same area included Song Sparrow, Swamp Sparrow, and Yellow-rumped Warblers that were feeding in the same habitat.

The bird hopped up from a lower, out of view position onto a perch near the top of a shrub, 2-2.5 ft above ground level. It held that position for ~20 seconds before it dropped back down. I tried to relocate the bird for 15 minutes, without success.

None observed.

Nelson's Sparrows were my main target species for my visit to Delta Park on this day. I was especially keen to look for subvirgatus, which I had never seen in Vermont (for certain) before. Walking from the parking area through the beach and rushes area, I was alerted by other birders to the presence of a Nelson's. I had good looks at it, a bird of the Interior (nelsoni) race, and I described it in my eBird report. Continuing on to the south, I reached an area where mudflats are backed up by low vegetation and a line of willows to the east, with occasional openings to the extensive marsh beyond. I stopped to listen to sparrow and warbler noises coming from the weeds and willows, when up popped this bird, in the open near the top of a low shrub 15' in front of me. I was on it immediately with my binoculars, while also quietly alerting a nearby birder. I had close, unobstructed views of the bird for about 20 seconds before it dropped down and never reappeared. My immediate impression was that this bird was definitely a Nelson's Sparrow, but a much grayer and washed-out looking version of this species. I was already noting in my head the contrasts between this bird and the Interior type of Nelson's Sparrow that I had studied just a few minutes earlier.

Relatively small sparrow compared to a nearby song Sparrow. Overall small-headed and short-tailed in appearance.

Gray crown stripe and gray cheek patch. The latter framed by a very muted/subdued, pale yellowish supercilium and malar region (in marked contrast to the bright buffy-orange color of these regions in the Interior form). Gray nape, continuous with gray coloration of back

Relatively small, conical bill, pale grayish in color. Legs dull pinkish in color.

Gray, continuous with gray on nape. Lacking contrast-- no distinct pale or dark stripes or streaks.

Grayish trend from nape and upper back continued on the lower back. This made the bird appear grayish overall, and much grayer and less contrasty than the Interior form of Nelson's Sparrow. The bird's rump was not seen.

I did not see the bird in flight. Primary projection was not noted. Pattern muted-- Scapulars and coverts grayish with indistinct darker streaks. Trending towards browner tones on the secondary and greater coverts, but not a warm look overall. No distinct wingbars.

Pale throat, very pale yellowish wash on breast, with diffuse pale gray streaks on breast. (In marked contrast to the much brighter buffy-orange color with fine streaks on the breast of Interior form.). Belly, flanks, undertail coverts pale with little visible color or streaking.

Short, dark tail.

Saltmarsh Sparrow was easily eliminated by this bird's lack of bold color in the supercilium and malar regions, by its overall grayish color, by its lack of color contrast or distinct markings on the upperparts, by its lack of distinct dark streaking on the underparts, and by my perception of this bird being relatively small-billed.

Nelson's Sparrow (Interior) race, A. n. nelsoni, was eliminated by this bird's marked contrasts with the former, notably: (1) Its muted, pale yellowish supercilium and malar region. (2) Its overall gray coloration on the upper back, lower back, and scapulars, which lacked any strongly contrasting marks such as the alternating whitish and dark streaks that are visible on the upperparts of nelsoni. (3) The weak yellowish wash and diffuse pale gray streaks on this bird's breast were quite different from the much brighter buffy-orange with fine streaks pattern seen on nelsoni.

The plumage was consistent with adult A. n. subvirgatus. I prepared this report from notes that I made mentally during the sighting, and that I recorded immediately after the sighting while submitting my eBird report.