Field Notes Dory Bell LOCATION: Alcatraz I., S.F. Co., CA. DATE: March 21, 1987 WEATHER: Patchy clouds; cool TIME: 10:28 On cistern, in blind. About 16 pairs around cement platform, and about 5 pairs sitting in middle area of platform. Most gulls resting, sitting & sleeping. One copulation seen on undirty building. Recording on data sheets the following. 10:38-10:58 - colony - most gulls resting, loafing. 10:58-10:18 : Watching one pair (#4) in cistern. Recording behavior of pair 4. At start, ♂ sitting on ground, head tucked. ♀ behind him standing. 11:03, ♀♂ moved to right, is now sitting too, at apparent nest site. Both sleeping. 11:06 ♀ stood up, preens, looks around, other gulls long calling & meowing. 11:07 ♀ chocked as another bird walked past. She then moved off the nest spot. 11:16 ♀ moved a foot to another spot, sat down. 11:18-11:38 - colony watching. Pairs 19+20 are very close in the platform near corner. Weather has become more overcast, colder. 11:36 - light rain, but sunny. 11:38-11:58 - observing pair 19 at close corner. One bird preening, other not present? The preening bird still standing. 11:45 - now the bird is just standing, looking around. (platform - ♀ stood up, walked around male while meowing) Immature Glaucous-winged flew over colony (2). 11:48 - confusing. Bird mdr obs. long called as another landed nearby on platform. The bird that landed then walked over to this bird meowing. Then it walked look over to another bird on platform and chocked with it. Meanwhile the bird under observation long called at pair 20 11:55- my bird now sat down. (11:55 Pair 4 is chocking). 11:57 - mate landed. Whole series of Aggs. Uprights at about 4 birds.. One ♀ on platform seems to be going around several males, preening. Chocked with one, then did lure away. 12:04- Pair 16 - one bird has another by wing, alarm calls, then went to fight.