Idaho Bird Records Committee Rarities Report Form
Rare Bird Report #: 38-B-07
Species: Brown Thrasher
Reporter: Jay Carlisle
6105 Kirkwood Rd
Boise, ID 83709
jaycarlisle@boisestate.edu
Other Observers: Carlos Valeris, Dianne Parrott, Dave Ewoldt, Jereme Sommers (IBO field assistants)
Date Report Prepared: 5-19-07
Date Sighting Occurred: 5-17-07
Locality of Observation: Camas NWR headquarters, Jefferson Co.
Habitat: riparian woodland
Conditions: clear, calm, and cool; I used Swarovski EL 10x42 binoculars and the sun was behind me & just rising, providing good lighting
Did you take notes? not at all
Did you consult a field guide or other reference work? after the observation
What guide(s) or reference(s) did you consult?
Sibley; National Geographic
Description: A robin-sized bird with a long tail and a thick, slightly decurved bill. Upperparts rufous (reddish-brown) with 2 prominent whitish wing bars. Underside whitish with prominent dark streaking on chest and belly. Song loud and consisting of double phrases.
Behavior: While opening a mist-net at sunrise (~600 AM), I heard the song and thought, "thrasher or mockingbird" then turned to see this bird climbing the outer branches of a Russian Olive at a distance of about 20 meters. It soon climbed to the dead upper branches of a cottonwood and continued to sing. I called Carlos over at this point and he was able to view & hear the bird. It sang from this general area (southern row of trees at the headquarters woodlot) for over 30 minutes, then was singing over the maintenance buildings/garages, and, later in the morning (about 1000 AM), was heard singing again from an area ~ 100 yards W of original encounter.
How and when did you positively identify the bird, and what clinched the identification for you? Right away due to the rich rufous coloration, long tail, decurved bill, size, and the song.
How did you eliminate similar species, and what were they? This is a very straight forward identification and the only similar-appearing species (Long-billed Thrasher) occurs only in southern Texas and Mexico. Long-billed has a more curved bill, grayer upperparts, and an orange eye (though I was unable to confirm eye color of this bird).
Experience with this species (and similar species): I have observed many hundreds, if not thousands, of Brown Thrashers especially in South Dakota (and surrounding states) and Connecticut. I have seen 2 previously in Idaho both at Camas NWR (in 2005 & 2006; see separate reports). I have seen at least 20 Long-billed Thrashers in Mexico and Texas.
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 (w/ a 10x zoom digital). While not award-winning photos, these are included to show the overall shape, the chest streaks, and the color.