PART I. ALBATROSS STUDIES 
A. Albatross Populations in the North Pacific Ocean 
During the 1957-58 nesting season, a census of albatrosses 
was conducted on all of the islands and atolls of the Leeward Chain. 
of the Hawaiian Islands, and also on the island of Kaula in the main 
group. Mr. Aylmer F. Robinson, of Makaweli, kindly furnished infor- 
mation on the status of albatrosses on the island of Niihau. The 
census therefore covered all known breeding colonies of albatrosses 
in the Hawaiian Archipelago. 
Outside the Hawaiian Islands, both Laysan albatrosses 
(Diomedea immutabilis) and black-footed albatrosses (D. nigripes) 
formerly nested on Wake, Marcus, and Johnston Islands. Albatrosses 
no longer occur on these islands, according to observers who have 
visited them in recent years. Laysan albatrosses once nested on 
Tori Shima in the Izu Islands, but were extirpated. Black-footed 
albatrosses also nested there, as they once did on Iwo Jima in the 
Volcano Islands, and on Muko Shima (and perhaps other islands) in 
the northern Bonin Islands; they were extirpated from the latter two 
archipelagos, but at least one pair was reported nesting on Tori Shima 
in January 1955. The only other recorded breeding station for black- 
footed albatrosses was Pokak (or Taongi) Atoll, in the northern Marshall 
Islands, where they no longer occur. 
It thus becomes apparent that (except for a few black-footed 
albatrosses on Tori Shima) both the Laysan albatross and the black- 
footed albatross have become extinct throughout their former breed- 
ing range outside the Hawaiian Archipelago, and at the present time 
are virtually confined as breeding species to the Leeward Chain of 
islands. The present census of albatross nesting populations there- 
fore represents essentially the total world population of these two 
species. 
Census Methods 
As described in detail in a previous report (Kenyon, et al. 
1958), depending on the terrain, two methods were used to determine 
the size of the nesting albatross population: (1) aerial surveys, and 
(2) ground counts. 
Aerial surveys were conducted at all of the islands in the 
Leeward Chain. The aircraft used were Navy UF-1 Grumman Albatross 
amphibians, flying at about 120 knots. Overlapping series of oblique 
photographs were taken at each island from altitudes of 200 to 500 
feet. Albatrosses were subsequently counted on these photographs. 
It was assumed, on the basis of ground counts made at Midway during 
the same season, that 25 percent of the albatrosses counted on these 
photographs were non-nesting birds. The number of nests present on any 
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