13 LHWolf 1967 Aimophila humeralis July 23 Canyon de Lobos, Par E. Guanacaste, Morlos, Mexico Then pair #3 flies uphill 20-30 yds. + chatter. followed by chatter from pair #1 which is just below tree where pair #3 chattered fine previously (07/13). 0655 - 2 birds flew downhill to tree of (07/13). one following other by 6-8 inches. flutter together around interior of tree before one lands 2-3 feet above other. upper one gives solo chatter then etc. then flies uphill 20+yds. followed by 2-3yds by other. 1st then to top of nearby 20+foot tree when flinging tail. flies to NW # 40 yds. to land in another 20+ foot tree near top. 2nd bird already there + chatter begins immediately. Both initially going to W + flicking right wings vigorously. Near end of performance outer bird - one that fluttering - turns to face E. Continues flicking right wing. During this chatter another pair - probably including one earlier chased - flies to top of 20+foot tree just vacated + chatter. Both wing flicking. 1st facing to NW, but then to face NW so at least one of each chattering pair is facing toward other pair. Then quiet + both pairs leave trees. 0709 - bird to near top of same 20+ foot tree downhill - + singing wheel, wheel, pause wheel, wheel. flew off uphill + heard pitza well uphill (50-75 yds) pitza approached when first bird landed + chatter, initiated by one pitza. then several pitza notes + one pair chattered to S of where just heard + another pair followed (introduced by one pitza) with chatter just to N. Then quiet. 0724 - keen chatter from tree #1. then after 30+ sec. delay sun bird flew into thick cover to NW + chatter. One of birds exposed on 60° stern - bare -