Sooty Tern 

 White Tern 



These species breed on tropical and sub- 

 tropical islands in the central or South Pacific 

 and migrate northward into the study area 

 where they are observed regularly enough to 

 say that the study area constitutes a part of 

 their normal winter or prebreeding range. The 

 islands of origin can be specified only for Juan 

 Fernandez Petrel (Mas Afuera of the Juan 

 Fernandez group, 500 miles west of Chile) and 

 for White-necked and Black-winged Petrels 

 (Kermadec Islands, 600 miles northeast of New 

 Zealand). The other species each breed on 

 many island groups so it is impossible to de- 

 termine their islands of origin. Birds in this 

 category are usually more abundant at the 

 southern end of the study area and usually 

 attain highest densities during the summer and 

 fall. 



4. Birds breeding in the South Pacific and 

 migrating through the study area. 



Mottled Petrel 

 White-winged Petrel 

 Pale-footed Shearwater 

 New Zealand Shearwater 

 Sooty Shearwater 

 Slender-billed Shearwater 

 Skua 



All but one species in this category breed 

 in the temperate zone in the New Zealand- 

 Australia region and migrate north in the spring 

 to the equivalent water zone in the North Pa- 

 cific. The exception, White-winged Petrel, 

 breeds in a marginally subtropical or tropical 

 climate and migrates to a transitional area 

 (subtropical-temperate) in the North Pacific. 

 Skuas and Sooty Shearwaters might also origi- 

 nate on the South American side of the Pacific, 

 although this is not likely. Birds in this cate- 

 gory reach greatest abundance in spring (April- 

 May) and fall (September-November) and are 

 totally or nearly absent in summer and winter. 

 One species. Slender-billed Shearwater, mi- 

 grates south through the study area only in the 

 fall. Its spring migration is restricted almost 

 entirely to the western Pacific. 



5. Birds breeding in the North Pacific and 

 wintering in the study area. 



Leach's Storm Petrel 

 Pomarine Jaeger 



These species breed in the subarctic and 

 arctic North Pacific in the summer and migrate 

 to, and through, the study area in the fall. A 

 substantial number remain in the study area 

 throughout the winter, although evidence is 

 clear that this wintering population is joined in 

 early spring, just before the return to their 

 northern breeding grounds, by birds that have 

 wintered farther south. 



6. Birds breeding in the North Pacific and 

 migrating through the study area. 



Golden Plover 

 Ruddy Turnstone 

 Bristle-thighed Curlew 

 Wandering Tattler 

 Sanderling 

 Red Phalarope 

 Pomarine Jaeger 

 Long-tailed Jaeger 

 Arctic Tern 



These species migrate through the study area 

 in springor fall between arctic breeding grounds 

 and islands (shore birds) or oceanic areas 

 (phalarope, jaeger, and tern) south of the study 

 area. Several species (shore birds and Poma- 

 rine Jaeger) also winter on or near the main 

 Hawaiian islands as well. None of the shore 

 birds observed in the study area was headed 

 toward the Hawaiian group. During spring mi- 

 gration months, about half of the Pomarine 

 Jaegers were heading north from areas south 

 of the study area. 



7. Birds recorded in the study area only 

 rarely. 



Black-browed Albatross 

 Fulmar 



Solander's Petrel 

 Pink-footed Shearwater 

 Fork-tailed Petrel 

 Gull sp. 



Gray-backed Tern 

 Blue-gray Noddy 

 Rock Dove 



These species are stragglers and were not 

 regularly recorded. Black-browed Albatross 

 and Solander's Petrel originate on islands south 

 of New Zealand and Lord Howe Island, respec- 

 tively; Fulmar, Fork-tailed Petrel, and the gull 

 species originate in the North Pacific; Pink- 

 footed Shearwater comes from the temperate 

 coast of South America, straggling west to the 



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