GRID AREA This area is defined by latitudes 32°30'N and 31°30'N, and by longitudes 117°45'W and 119°15'W. It was entered at 1200 hours on 14 December and left at 1700 hours on 19 December giving a total coverage of 55 hours and over 426 miles of diurnal observations. A total of 594 birds (10.8 per hour) was recorded within this area (See TABLE III). This is over twice the density found in the Northern Grid (4.27 per hour) at the same time. TABLE III DIURNAL ABUNDANCE OF SPECIES GROUPS Species Group Number of Birds Birds Per Hour Duck 3 0.05 Albatross-Shearwater 80 1.45 Storm Petrel 5 0.09 Tropicbird 2 0.04 Pelican-cormorant 22 0.40 Phalarope 42 0.76 Jaeger 11 0.20 Gull 389 7.07 Tern 3 0.05 Alcid 15 0.27 Miscellaneous 22 0.40 Total 594 10.80 Ducks: The only birds observed were three Red-breasted Mergansers (Mergus serrator). Albatross-Shearwater: This group is well represented in these waters although the diversity of species is not nearly as great as that found in the Central Pacific. All of the species recorded are likely to occur in that latter area and indeed two are known to occur there in large numbers (Black-footed Albatross and Sooty Shearwater).