FIELD NOTES Doug BELL LOCATION: Alcatraz I., S.F. Bay, (A. DATE: April 26, 1987 TIME: 9:30 - 12:13 Weather: lifting fog, sun. Moderate Wind. Tide: Low, but incoming. Rock .75m exposed. Nearly covered at 12:30. At blind on cistern - 9:31: 29 gulls on perimeter, 10 on platform. When Maren and I first arrived-lots of gull activity on the cistern-fights, grappling, etc. Recorded gulls from 9:30-10:00. at 10:00: 30 gulls on perimeter, 10 on platform. 10:03 Colony: female 31 on nest, was attacked by neighboring 5, she jumped off nest, jabbed at the 5 and long called. 5 then mewed, ran over to mate, in territory 5, and choked. Several near-adults with black tails flying around. 10:15: watched pair 34. (Copulation off cistern by unknown pair). 10:18 - mate flew off. The other bird then flew over to territory 1, and was later joined by mate. Both long called, mewed, and jumped off ledge to shelf where they commenced choking. This was in response to intruders. It appears that the pair 34 is really undecided about whether to nest in territory 34 or territory 1, as they were also defending into 34 earlier. Six Western Kingbirds were seen on the cistern-must have been just passing thru. (Pair 23 copulated)10:40: watching Pair 19. 32 gulls on perimeter, 9 on platform. Pair 19 choked to 10:42, then preened. (Copulation up on bowels). (Pair 18 copulated) - the copulation seemed to stimulate Pair 19, as they also attempted to copulate. 10:46: female wandering about, pecking at pebbles. [10:47 Copulation on I8 roof.] 10:50: both birds sitting, end of pair 19 observations. 10:50 - watching colony. 11:00 - court feed: fish (pair 31). 12:00 - two more courtship feeds - both times-small fish. 12:13- watching colony 25 gulls on perimeter, 8 on platform. Wind