ford 2887 Gymnogyps californianus February 13, 1946 Hopper Canyon, Cal. f. open ledge . 3:30, 2 more adults spiraled down & landed about 1 minute apart. Whitewash Ledge now appears: imm. - lone adult mmss eeee 3:33, two more adults here; one from cliff top & 1 from top of Roast Tree. The flapping of this latter made a high "woot woot" -1mm. sound of snappy quality. Corrections - 8 imm.; me with adult atop cliff-the imm. flapped lightly while facing adult as if "sleing" for food. Lone adult Two adults took off & glided down the canyon at 3:32+. Within 3 minutes, all but 6 (4 of these were imm.) were off & circling over me. They gradually rose, broke into several groups, & rejoined over Arundell Ridge where I counted 18 in air & 6 on cliff (24 total!!). I hiked fast up North Slope to avoid further distur- bance of the birds. At 3:40 one alighted on Whitewash Ledge. About 3:45 saw one atop a P.S. on Arundell Ridge. 7:00-16 in one branch over Pyramid Canyon - only 8 by 4:05. There was a fair breeze up the canyon at 4:05; temp. 50°F.; sky clear. I continued up the slope. 10cm- dors continued to mill together here & there - occa- sionally 200' above me. At 4:25 they were over Pyr- amid Canyon. at 4:30 I could spot more. at 50m. Breeze light. Roast tree & drove to Fillmore.