Pelagic studies of seabirds in the central and eastern Pacific Ocean

Abstract

Seven papers by various authors on the pelagic distribution of several seabirds in the central and eastern Pacific Ocean based largely on the researches of the Pacific Ocean Biological Survey Program; 1963-1968. "Introduction," by Patrick J. Gould, introduces these and future papers in this series. He discusses the methods and procedures used by the POBSP in gathering and recording data on observations of seabirds, outlines the areas under surveillance, and provides a general account of the oceanography and marine biology of the areas under discussion as a background to understanding the movements of seabirds in relation to their environment. "Sooty Tern (Sterna fuscata)," by Patrick J. Gould, presents the POBSP's records of this most abundant tropical and subtropical Pacific species. Its distribution at sea depends on erratic food availability, location of breeding islands, breeding schedule, and postbreeding dispersal patterns. "Wedge-tailed Shearwater (Puffinus pacificus)," by Warren B. King, gives data on the distribution of the northern, predominantly white-breasted and the southern, dark-breasted morphs of this species. Subtropical populations migrate extensively, for example between the Hawaiian Islands and the Pacific coast of Middle America; tropical populations are apparently nonmigratory. "Black-footed Albatross (Diomedea nigripes)," by Gerald A. Sanger, discusses the distribution and frequency of sightings on a seasonal basis of this ship-following seabird, both in general terms throughout its range and in detail in certain areas, for example, the CalCOFI study covering an eight year period off California and Baja California. Its winter range overlaps largely with, but lies slightly to the south of, its summer range. "Laysan Albatross (Diomedea immutabilis)," by Gerald A. Sanger, analyzes observations of this species and relates its seasonal distribution and abundance to its oceanographic environment. This species is more abundant in the western and central Pacific, whereas the Black-footed Albatross is more abundant in the central and eastern Pacific. "The Storm Petrels (Hydrobatidae)," by Richard S. Crossin, summarizes the POBSP's data on eighteen species or subspecies of storm petrels based on sightings and collected specimens. Pelagic distribution is related to breeding cycles, location of breeding sites, and marine environment. "Red-tailed Tropicbird (Phaethon rubricauda)," by Patrick J. Gould, Warren B. King, and Gerald A. Sanger, discusses seasonal distribution and abundance of this species relative to its breeding cycle. This species disperses widely from its breeding islands, for example, from the Hawaiian Islands to the Pacific coast of Middle America. "Recoveries of Banded Laysan Albatrosses (Diomedea immutabilis) and Black-footed Albatrosses (D. nigripes) in the Pacific Ocean," by Chandler S. Robbins and Dale W. Rice, summarizes the seasonal distribution of pelagic recoveries of 324 banded Laysan Albatrosses and 399 banded Black-footed Albatrosses. Different age groups of each species concentrate in somewhat different areas, and, although range overlap between species is almost complete, each has its own distinctive seasonal distribution pattern.