California condor Eben Macmillan 25 November 1963 brush just across the canyon from us as we entered the steep climb of the Spring Canyon trail. We saw this Stags tracks in the damp Ground where it, or another large deer, had come down this trail from the top of the ridge just after the last rain. A lion track also was formed in this trail, coming down also, about the same time after the last rain. We reached the top of Hopper Rim about 30 minutes before Sunset. The area along the Coast, the Islands of the Santa Barbara Channel and all mountainous areas were extremely clear and free of smog. A very strong wind was blowing over this tin from the east. White-throated Swifts that were all passing up over this rim heading northeast were able to pass onward, into this blast, with little trouble seeming to roll through the strongest currents that were developing at the very cross of the rim from volumes of air rushing up out of Hopper Canyon and compressing at the top of the ridge. This rolling motion gave the appearance of a swimmer (human) doing one of the crawl strokes & only the birds (Swifts) would make up to five or six wingbeats during the time they would be tipped over to one side or the other. These Swifts would come over the pass about 50 or 100 feet high (above the crest). There were more than 100 passed by the Station where we stood in about 20 minutes. Later as the sun was setting swifts were joined by Robins coming from the Sesepe over into Hopper Canyon. The robins also did well against the strong wind but they would drop down into Hopper Canyon as soon as they topped the Hopper rim at tree-top height. A thorough check was made of any boosting areas—