Rare Bird Report #: 8-B-03

Idaho Bird Records Committee Rarities Report Form

 

Species: Tennessee Warbler (I did not see this bird – only photos)

Reporter: Jay Carlisle

6105 Kirkwood Rd

Boise, ID 83709

jaycarlisle@boisestate.edu

Other Observers: Ryan Brady, Khara Strum, Seth Martin, Carly Moore

Date Report Prepared: 12-11-06

Date Sighting Occurred:  8-31-03 (capture)

Locality of Observation: Lucky Peak (Boise Foothills), Ada Co.

Habitat: montane deciduous shrubland bordered by coniferous forest

Conditions: I do not know

Did you take notes?  not at all

Did you consult a field guide or other reference work? during the observation

What guide(s) or reference(s) did you consult?

Pyle’s 1997 ‘The Identification Guide to North American Birds’, National Geographic

Description: A small Vermivora warbler with a slender bill; a bright yellowish/greenish back and head; a distinct, dark eye-line splitting a broken eye-ring; a yellow wash on the throat, upper chest, and flanks; whitish undertail coverts and belly; and a relatively short tail (as compared to similar appearing Vermivora warblers like Orange-crowned).  Wing: 60mm; Tail: 42mm.

Based on incomplete skull development and plumage, this bird was identified as an immature (hatch-year).

Behavior: none observed as this was a bird captured as part of a standardized bird migration study

How and when did you positively identify the bird, and what clinched the identification for you?  Clinching features included the whitish undertail coverts, bright greenish-yellow coloration to back and head, and the dark eye-line. Additionally, the relatively short tail was another diagnostic field mark.

How did you eliminate similar species, and what were they? Orange-crowned Warbler (always has yellow undertail) is the most likely to be confused with this species, especially for immature Tennessee Warblers which are a brighter yellow than all subspecies of Orange-crowned.  However, the combination of the features mentioned in the above section all help to separate from Orange-crowned and other Vermivora species.  Additionally, Orange-crowned Warblers have a longer tail and an Orange-crowned Warbler with a 60mm wing is most likely to have a tail measuring 49 or 50 mm (as opposed to 42mm).

Experience with this species (and similar species): Ryan Brady, who made the identification, has extensive experience with Tennessee Warblers in the Midwest (Wisconsin) and Orange-crowned Warblers in Idaho and elsewhere.  

General birding experience: Ryan has extensive experience; 10+ years

Were photo(s), video, and/or audio obtained by you? (If yes, please include or attach)    Yes, but not by me.  See 2 attached photos taken by Ryan Brady.