Another interesting tidbit from our birding friends in the keystone state. -----Original Message----- From: Bird discussion list for Pennsylvania [mailto:[email protected]] On Behalf Of Grant Stevenson Sent: Tuesday, October 17, 2006 11:40 PM To: [email protected] Subject: [PABIRDS] Wax Birds
Just a note: Tree Swallows, Pine Warblers, and Yellow-rumped Warblers=20 have in their digestive systems the ability to digest wax berries like=20 barberries, poison-ivy, dogwood, wild grape, Virginia creeper, and sumac like Cedar Waxings, Phainopepla, N. Flickers, and Downy Woodpeckers=20 slightly have the capability to do. Tree Swallows' ability to digest=20 recoated beeswax exocarps paralleled that of Yellow-rumped Warblers.=20 This study's results may be a stimilus for winter birders to look in=20 unlikely spots in North America at unlikely times for these birds,=20 depending on the unmonitored crop-size of these plants. For more=20 information, see Place, A.R., and E.W. Stiles (1992, Living off the wax=20 of the land: bayberries and Yellow-rumped Warblers, THE AUK 109(2):=20 334-345; obtain via PDF from SORA on BIRDNET, www.nmnh.si.edu/BIRDNET/.=20 Place inside "keywords" YELLOW-RUMPED WARBLER. Also has YRW study from=20 Presque Isle.). I welcome any corrections, from professors or "amateurs". Happy birding, Grant Stevenson Bethlehem, Leheigh County, PA [email protected]
