On six surveys of Swain’s Island in 1966 and 1967, field workers of the Smithsonian Institution’s Pacific Ocean Biological Survey Program recorded 16 species of birds: 9 central Pacific seabirds, 5 Arctic shorebird migrants, and 2 migrants from the southwest Pacific. Three species of seabirds (brown noddy, black noddy, and white tern) breed on the island and a fourth (white-tailed tropicbird) probably does so. The other species of seabirds recorded from the island (sooty tern, black-naped tern, frigatebird sp., red-tailed tropicbird, and red-footed booby) probably occur on the island only as visitants. Three of the shorebirds (golden plover, ruddy turnstone, and wandering tattler) are common and regular migrants to the island; the other two species (bristle-thighed curlew, sanderling) occur much less frequently and in much smaller numbers. One of the two migrants from the southwest Pacific, the reef heron, is apparently of irregular or uncommon occurrence while the other, the New Zealand cuckoo, is present in small to moderate numbers throughout much of the year.
Roger B. Clapp (Sun,) studied this question.