Albatrosses Residing on the Senkaku Islands (1979: Former Okinawa Development Agency)

Historically, seabirds such as the short-tailed albatross, black-footed albatross, sooty tern, and brown booby have flourished on the Senkaku Islands. (Ref. 1)

The short-tailed albatross, which is a special natural monument in Japan, was widely distributed across islands of the Northwestern Pacific until about 150 years ago, when there are believed to have been at least several hundred thousand of the birds. However, they were indiscriminately captured from the late nineteenth century through the first half of the twentieth century (Ref. 2), when they reached the brink of extinction, with populations believed to have dropped as low as 45 birds. (Ref. 3)

At present there are only two short-tailed albatross breeding sites in the entire world, the Izu Islands (Torishima Island) and the Senkaku Islands (Kitakojima Island and Minamikojima Island). (However, one breeding pair was identified in 2011 and 2012 on Midway Atoll in the Pacific.) (Ref. 4)

Senkaku Island short-tailed albatrosses were overharvested for their down starting in 1891. In 1963 the Committee for the Preservation of Cultural Assets in the Ryukyus entrusted Takara Tetsuo (Professor at the University of the Ryukyus) to form a survey team and conduct a survey, but no report of short-tailed albatross sightings was produced. (Ref. 5)

However, they were later sighted again for the first time in 71 years, during the 1971 University of the Ryukyus Academic Survey (report by Ikehara and Shimajana). (Ref. 6)

In Japan, the short-tailed albatross is designated as a special natural monument, as well as a protected species under the "Act on Conservation of Endangered Species of Wild Fauna and Flora." (Ref. 7)

The short-tailed albatross population of Torishima Island in the Izu Islands, due to many years of conservation efforts on the part of the Yamashina Institute for Ornithology, Hasegawa Hiroshi (Professor at Toho University), and other researchers, has been restored to an estimated number of over 3,000 birds as of 2012. (Ref. 8)

However, a population genetics study of the short-tailed albatross published in 2011 reported that the birds of these two remaining breeding grounds in the Senkaku and Izu Islands are distinct subpopulations, and that there is a strong probability that they are distinct species. That report also argues that it is therefore vital to rapidly perform a survey of short-tailed albatross breeding pairs in the Senkaku Islands and to take urgent measures to protect them. (Ref. 9)

 

 

tit

Ref.1 : Senkaku Islands Document Material Compilation Association, Senkaku kenkyu: Senkaku Shoto kaiiki no gyogyo ni kansuru chosa hokoku--Okinawaken ni okeru senzen-Nihon fukki (1972 nen) no ugoki (Senkaku Research: Survey Report on Fishing in the Senkaku Islands Territorial Waters, Examining Developments in Okinawa Prefecture from the Prewar Era Until the 1972 Reversion to Japan), based on a fiscal 2009 Japan Foundation Research Grant (2009).

Ref.2 :Yamashina Institute for Ornithology, "Ahodori fukkatsu e no tenbo" (Outlook for Short-tailed Albatross Revival), posted on April 28, 2011, on the Yamashina Institute for Ornithology website.

Ref.3 : Kuroo Masaki, Komekawa Hiromichi, Saito Shigeru, Matsuba Chikako, Hasegawa Hiroshi, "Ahodori no shudan idengaku kyodo kenkyu no happyo" (Short-tailed Albatross Population Genetics Study: Joint Study Report), presented at the annual meeting for the Ornithological Society of Japan on September 16, 2002, and posted in Ahodori fukkatsu e no kiseki (Trajectory of  Short-tailed Albatross Revival), Toho University Virtual Laboratory website.

Ref.4 :Hasegawa Hiroshi, "Middowe kansho kara ahodori no hina ga kotoshi mo sudatsu" (Short-tailed Albatross chick left the nest again this year, at Midway Atoll), posted on July 6, 2012, in Ahodori fukkatsu e no kiseki (Trajectory of Short-tailed Albatross Revival), Toho University Virtual Laboratory website.

Ref.5 :Takara Tetsuo, "Senkaku no ahodori o saguru" (Searching for the Short-tailed Albatross of the Senkakus), in Minami to kita, Assistance Association for Okinawa and Ogasawara Islands quarterly, no. 26 (March 1964). Collected in: Senkaku Islands Document Material Compilation Association, Senkaku kenkyu takara gakujutsu chosadan shiryoshu (Senkaku Research Takara Academic Research Group Materials), vol. 1 (October 14, 2007), pp. 161-169.)

Ref.6 :Ikehara Sadao and Shimojana Matsuei, "Senkaku Retto no rikusei shokubutsu" (Land Animals of the Senkaku Islands), in Senkaku Retto gakujutsu chosa hokoku (The Senkaku Islands Academic Survey Report) (Okinawa: University of the Ryukyus, July 1971), p. 85.

Ref.7 :Hasegawa Hiroshi, Ahodori fukkatsu e no kiseki (Trajectory of Short-tailed Albatross Revival), Toho University Virtual Laboratory website.

Ref.8 :Hasegawa Hiroshi, "Dai 108 kai Torishima okinotayu chosa hokoku" (Report of the 108th Survey on the Torishima Island short-tailed albatross), posted on June 4, 2012, in Ahodori fukkatsu e no kiseki (Trajectory of Short-tailed Albatross Revival), Toho University Virtual Laboratory website.

Ref.9 :Eda Masaki, Koike Hiroko, Kuroo Masaki, Mihara Shozo, Hasegawa Hiroshi, and Higuchi Hiroyoshi, "Inferring the Ancient Population Structure of the Vulnerable Short-tailed Albatross Phoebastria Albatrus, Combining Ancient DNA, Stable Isotope, and Morphometric Analyses of Archaeological Samples" Conservation Genetics 13 (2012), pp. 143-151.

 

 

tit