perside of tail : darkish Underside of tail : whitish - outlined by dark borders slightly forked Legs dark Behavior : Moving slowly in top of locust tree when I first located it. Singing about once every 30 seconds. Watched in canopy for about 15 minutes. Eventually saw all field marks. Later found foraging in low branches of Am. Elm about 15' off ground - all field marks again seen clearly. Seemed to move much more slowly than other warbles Voice : I first located this bird by its high, thin song which I said was either going to be Bay-breasted, Blackpoll, or Cape May. The song consisted of a about 6-7 sturred thin notes - quality of Golden-crowned Kinglet call. Habitat : Cottonwood-Am. Elm oasis in middle of rocky- sagebrush desert How identification was decided - elimination of similar species chestnut dark brown creamy buff (not white as shown in fieldguide) chestnut white white I really can't think of anything to eliminate it from Chestnut-sided Warbler has white throat, yellow crown Prior experience with this species: once in fall in Calif. ~ 20 times in breed. plum. in Mass. This description written from notes made during observation [check] notes made after observation [check] memory Others seeing the bird (addresses of two): John + Susanne Luther, Don Roberson, Joe Marlan, Garth Alton, Dave Rudholm. Signed Date 6-4-74