IBRC Rare Bird Report Form:

Rare Bird Report #:  3-A-07

Species: Wood Thrush

Reporter: Jay Carlisle

6105 Kirkwood Rd

Boise, ID 83709

jaycarlisle@boisestate.edu

Other Observers: Jake Briggs, Carlos Valeris, Jereme Sommers (IBO field assistants); Theresa Mathis (BLM – Idaho Falls); many other Idaho birders

Date Report Prepared: 5-19-07 (updated 7-6-07)

Date Sighting Occurred: 5-19-07 (capture); recaptured on 5-20-07 (gained 4.4 grams!); recaptured daily through 5-22 and again on 5-25 (stable in mass since original mass gain); then heard and/or seen daily through at least 6-14-07 (we left the area on the June 15th at the conclusion of the study)

Locality of Observation: Camas NWR headquarters, Jefferson Co.

Habitat: riparian woodland

Conditions: clear, cool, and calm

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’, Sibley, National Geographic

Description: A plump thrush with a rusty head and back; a whitish chest with many black spots; and a short tail.

Based on plumage & feather wear, this bird was identified as a 1-year old (second-calendar-year).

Behavior: this was a bird captured as part of a standardized bird migration study. The bird was quite secretive the first couple of days and went undetected outside of the captures. On day 3 (5-21), I heard the alarm call note (a 4-5 note rapid sequence) while opening one of our nets (net 7, SW of office) but did not see the bird. Later that day, several of us went looking and found the bird (quite skittish) – it seemed to center in this area between 20-22 May. On day 5 (May 23) it began singing from deep within Box Elder trees along Camas Creek (now dry) near the observation platform and it continued singing and occupying this area through May 25. From May 26 – June 1, it was again heard (sometimes seen) daily from the area around net #7 but was not captured again (must have finally learned the net location!). From June 3 to June 14 it was heard (and less commonly seen) regularly but not daily. Thus, because most passage migrants stopping over stay only for a few days, the fact that this bird stayed for at least 26 days suggests that it took up summer residence …. However, since we finished our study on June 15, I do not know if has continued since.

How and when did you positively identify the bird, and what clinched the identification for you? Clinching features included the reddish uppersides, the distinct spotting, and the short tail.

How did you eliminate similar species, and what were they? Catharus thrushes are all somewhat similar in size & coloration but differ in proportions from Wood Thrush, appearing longer tailed, and also have less distinct spotting that is restricted to the breast. Of the Catharus thrushes, Veery is most similar due to its reddish coloration but this is a much more subdued color than the relatively bright upperparts of the Wood Thrush.

Experience with this species (and similar species): I have observed hundreds to thousands of Wood (especially Connecticut, Louisiana, and South Dakota), Hermit, and Swainson’s Thrushes and tens to hundreds of Veery but this is the first Wood Thrush I have observed in Idaho.

General birding experience: extensive; 14+ years in US and Latin America

Were photo(s), video, and/or audio obtained by you? (If yes, please include or attach) Yes, by Carlos Valeris. Also, Rob Larrañaga has a video clip of a Brown Thrasher observed on 5-24-07 in which the song of the Wood Thrush can be heard in the background.