Petelka 1950 A. coeruleans Oct. 29 Wildcat Canyon the other individual turned back after getting to about ½ the distance. Both came from the west side, near the ridge top. a note, heard only rarely in my experience, seemed today to prove to be a threat note used in aggressive territorial behavior. This I have transcribed as kr-rr-shk. It is a harsh, somewhat nasal note, with a sneeze, yet not strongly sibilant. It was heard three times. One it was given just before a chase; in the other two instances, the {from movements of the birds, indications} were that the note was again given as part of aggressive territorial behavior. Once a scrub jay chased a Steller jay, which flew upward and away a short distance (40 ft. t). There were only 2 or 3 Steller jays in the canyon between The shooting range and the small lake.