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Transcription
While off the east coast of Guadalupe Island, on 26 April, we encountered a flock of 11 birds flying north and paralleling the island about two miles off shore.
Pomarine Jaeger Stercorarius pomarinus 4
The Jaegers were seen on two successive days. All were light-phase adult birds with twisted central retrices. Two of these birds were attracted to fish that we caught on the free vehicle gear and floating on the surface. They were not observed to feed.
Sterna sp. 3
One bird was seen on 22 May at 30°56'N, 117°12'W, and two others on 24 May at 29°38', 117°26' (sightings 50 miles and 85 miles off Baja, respectively). The birds were not well observed, but were small with gray backs and were probably either Forster or Common Terns.
Red Phalarope Phalaropus fulicarius 338
The birds were seen during both parts of the trip. However, the birds seen during the Washington cruise were apparently not in migration. Many of these birds were still in winter plumage, some were molting, and a few were in nuptial plumage. But by 28 April the birds had begun moving north and greater proportions of these birds were in molting or in the real breeding plumage. Apparently the birds molt the body feathers in migration. All birds handled in Bering Sea in May and June last year had completed the molt. But the question arises, do the birds ever reach the breeding grounds with the molt still in progress?
As was noted by Harrington who was working off central California from 18 to 25 April, 1967, the distribution of Red Phalaropes is local. This also seems to be true of the birds in migration. We encountered fronts or waves of birds moving north in flocks of 3 to 25 birds. An example: on 4 May north of Guadalupe Island in a 13-minute period, six flocks totaling 73 birds were seen. It was then 47 minutes before another group was encountered.
Xantus Murrelet Endomychura hypoleuca 6
The small number of alcid s recorded probably does not reflect actual densities, as the birds sit on the water and spend much time feeding under water. The birds are seen only when flushed by the approaching ship. Also, the birds were breeding on Guadalupe Island at this time and may not wander far from the island to feed. This is true of alcid s breeding on St. George Island, Bering Sea. Here there will be concentrations of millions of alcid s feeding along tide rips within five miles of the island.