FIELD NOTES Doug Bell Date: 25 April 1986 LOCATION: Alcatraz Island, S.F. Co., Calif. WEATHER: clear, sunny. Moderate wind. TIME: 12:00-14:00 In for a quick check of the island. Paired birds (Western Gulls) everywhere. Ray Pierotti, Katy Muir, Emilie Martens with me. Katy and I watched a pair of gulls go through a mutual courtship feed, on the Parade Grounds. The pair was Upon landing, they chaff choked on-site. disturbed by our presence, but came back to their territory. Female began head begging. The male, a big bird, old looking, went through some regurgitating motions after about 10 seconds. He then coughed up a small fish (as long as bill) into his bill, mouthed it, then swallowed it again. He repeated this twice more over the next minute. The female also coughed up a small fish, only to swallow it again. Both birds took off, flew around, then landed on territory again. Male sat down. Female begged a couple times, then gave up. Began preening. Overall, the gulls are giving more alarm calls at our approaches. Checked Parade Grounds, Western Perimeter, and Cistern and power houses. Only 3 nests on Cistern had eggs: two nests w/1 egg each, one nest w/2 eggs. Counted 50 gulls soaring about cistern while the 3 others checked the nests. No eggs on Industry Building roof (west of Cistern). Watched the roof for about 20 minutes, but saw no courtship feeding. Only one minor territory dispute where one bird held up wings & walked over to another who had just landed. The other bird walked about 2 yards away from the [illegible] threatening bird.