California condor Eben Dychmillan 18 February 1964 or elevating, perpendicularly, for great distances of perhaps three hundred feet at a time. While watching this condor, and the other large birds hereabouts, sitting on the wind above Hopper mountain, there appeared to be one small area that lay near the top and above a swale that faced into the wind, a dead-air space created difficulty for them to maneuver over. The first bird I saw pass over this area was an immature red-tailed hawk. When this hawk hit this area it commenced beating its wings more rapidly than I had ever observed these hawks do so before, and it appeared for a time that it was going to be forced to land in order to get out of trouble; but it did make its way out after about fifteen seconds had passed. Later I saw the young condor get trapped over this same dead-air space. The young condor experienced considerable difficulty in setting past this space having to pump its wings quite fast, but did seem to be more maneuverable in this situation than was the hawk that is mentioned above. At 4:17 p.m. an immature condor came from the north, down Hopper rim, and remained sitting on the wind above Hopper mountain. This immature condor appeared the same as did the bird that was here only a few minutes before. It had considerable muddy white under the wings with the patch of longer muddy-white feathers next to the body. The head appeared dark. The color was soft dark-brown with no sheen. The wings and tail were without feather gaps and the tail was long. When Ian and I were here in Sulphur Creek with Carl Buchheister on February 2 and 3 we saw an immature condor about Hopper mountain that kept to