EAC 4, Shearwater, February-March 1967
Page 47
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Transcription
- 10 - Jaegers (41) Jaegers were also quite abundant in the southern section of the non-grid, specifically in the area with large concentrations of Kittiwakes and other feeding birds. They were frequently observed harrassing the Kittiwakes and were often successful in causing a regurgitation. Thirty-three were recorded as Pomarine and 8 as Jaeger sp. Since light conditions made identification difficult, it is probable that Parasitic Jaegers were also present though none were positively identified. Only one Jaeger was sighted in the northern section. Red Phalarope Red Phalaropes (9) appeared to be well-scattered over the southern section where observations were made. These were our first non-grid records, but prob- ablely because we were so far from land and had not made a day survey in this specific area. Each bird was observed singly, one being in a flock of Kittiwakes. None were seen in the northern section. Gulls During the first day of non-grid observations, as we passed through the Santa Barbara Channel, no Herring Gulls were identified. The next day, as the grid track was neared and we were distant from land, Herring Gulls (16) were following the ship. It appears that the Herring Gull is being out-competed near land as indicated by the large numbers of other gulls. In the Eastern Pacific it seems to be a pelagic gull. Judging from the previous cruises and this one, the Herring Gull commonly follows at sea but decreases in number as land nears and other gulls appear. In the southern section the Herring Gull (31) was common but land was distant and only a few other kinds of gulls were sighted (i.e., California, Western, Ring-billed). Adults outnumbered immatures 4:1 in the north, 15:1 in the south. In the northern section California (30),