Worm-eating Warbler, Desert Museum: 11/07/2009

After receiving an email in the Rare Bird Alert inbox yesterday, I ran over to the Arizona-Sonoran Desert Museum today in an attempt to get some documentation-worthy photos of a WORM-EATING WARBLER. Susan Parker-Hotchkiss, a docent at the Museum, discovered the bird on November 5. Good find, Susan!

Morgan Jackson borrowed my camera while I was off getting coffee...and got this nicely framed shot of the bird eyeing up the dead leaves upon which it feeds (on the wintering grounds). As silly as the word sounds, I believe this bird's underparts coloration is most accurately described as "taupe."

One study of this bird's habits on its wintering grounds in Belize (Greenberg 1987) found that Worm-eating Warblers forage "primarily at dead curled leaves in forest understory; 75% of maneuvers by 107 individuals directed toward dead leaves.... Picks, probes, and gleans from hanging dead leaves, vine tangles, twigs, and occasionally green leaves. Most commonly forages on dead leaves; searches intensively for 10–15 s in each tangle before moving on."

Distinctive crown stripes observed from the back and topside:

And for those of you who just need to have a full body shot, this is the only one I managed to obtain. Blurry, but it leaves zero doubt as to the bird's identity:

Most literature indicates that they are rarely seen on the ground, but given the limited optimal foraging substrate in this location, I don't think the bird had much choice!

When "Finding Birds in Southeastern Arizona" was updated 2 years ago, there were about 35 total records for this bird in the region.

Good birding,
John Yerger
Tucson, AZ
Senior Guide
Adventure Birding Company

Literature cited:
Greenberg, R. 1987. Seasonal foraging specialization in the Worm-eating Warbler. Condor 89:158-168.


Matt! and Sarah said...

Dude, you are on a roll! Nice shots of the WEWA. If it sticks around through the beginning of next week, maybe I'll have a chance to go look. It'd be a lifer for me, just like the Magnolia was this morning. later!

Nate Dias said...

Worm-eating Warblers also habitually glean in dead-leaf clusters on the breeding grounds.

They do it even more during fall migration.