2) Further decrease of Leach Storm Petrel and Red Phalarope. 3) High numbers of Jaegers concentrated in the northeast. 4) Arctic Terns passing south through the grid area. 5) Numbers of "lost" landbirds. General: Eastern Grid Survey # Overall linear Density 19-29 July 10 .411 Birds/linear mile 8-16 August 11 .756 26 August - 4 September 12 .404 11-22 September 13 .521 .527 Average. Sectional average linear density EGS 11, 12, 13: .629 ' 1.242 ' 1.580 .123 ' .331 ' .515 .223 ' .214 ' .421 The relatively consistent survey densities belie the fact that a fairly large general changeover in grid avifauna has occurred from July to September. During the mid-summer surveys (#s 10 and 11) Storm Petrels and Phalaropes accounted for about three-fourths of the total grid birds. During the present survey Storm Petrels and Phalaropes accounted for less than one-quarter of the total. The static summer population of post or non-breeding birds has largely disappeared. In its place migrant species, notably Sooty Shearwaters, Terns, Ducks and various landbirds have appeared. The bird distribution within the grid has remained about the same, concentrations being found in the north, northeast, and east portions on all four surveys. At least three factors contribute to this general distribution pattern: 1) the proximity to land; 2) oceanographic features; i.e., upwellings and current structure in the associated areas; 3) tendency for migrant species to parallel the coast and thus cross the northeast grid corner. (See Sooty Shearwater; an important exception to the last). Bathythermographic data were collected and analyzed by Dr. Pyle. The results appear to be quite relevant to certain ornitho- logical features, but will be treated in detail elsewhere.