The Yamashina Institute for Ornithology transported 10 Short-tailed Albatross chicks, which have been designated an endangered species, from a breeding site on Torishima Island, part of the Izu islands, to Mukojima Island, which is part of the Ogasawara islands, this February. After a 3 month artificial raising program all the individuals had successfully left the nest by May 25. It is hoped that as all the artificially raised chicks had been there for a long time before leaving the nest they would consider Mukojima Island to be their home ground and return there to breed in a few years time.

A previous example of chick transportation includes 1,000 hole-nesting Atlantic Puffin chicks being transported about 1,610km from Newfoundland in Canada to Eastern Egg Rock and Seal Island in Maine, the U.S., and then artificially raised. The transported chicks started breeding 8 years after transportation at both the aforementioned locations, with the number of breeding pairs having increased from 16 to 19 on Eastern Egg Rock and to 40 on Seal Island.

Examples of transporting ground-nesting seabird chicks are limited: the Red-footed Booby in Hawaii, the Australian Gannet in Australia, the New Zealand Fairy Tern in New Zealand, etc, with this being the first attempt for albatrossess.

It is estimated that there is a total of about 2,500 Short-tailed Albatrosses, which were born on Torishima Island and the Senkaku islands, globally. The following reasons were a major destabilizing factor in the recovery of this species: Torishima Island is a volcanic island that has the risk of eruption and the Senkaku islands are involved in a territorial issue that makes research and preservation activities difficult. In recent years their recovery on Torishima Island has been going well, therefore making the plan to reintroduce them to one of their old breeding sites so as to produce a third site a real possibility for the parties concerned. Some background to this reintroduction plan was being contacted by the U.S. government. The Short-tailed Albatrosses lives within the territorial waters of the U.S., such as the offshore of Alaska during the non-breeding season, and was specified an endangered species by them. The government needs to make and execute a recovery plan using concrete numerical targets within a certain period in accordance with their domestic law when anything is specified an endangered species. And hence the U.S. government requested Japan to participate in the planning stage for recovery of this species.

The recovery planning team set very concrete targets in addition to numerical ones for total breeding individuals and their increase ratio: The candidate site must have at least three collective breeding grounds with at least two of them being non-volcanic. Extremely strict restrictions, for example nearby fishing grounds being closed if even a small number of the albatrosses are caught in the fishing nets used by the fishery industry off the coast of Alaska, will stay in place until the targets have been achieved and the species removed from the endangered species list.

This accounts for the reason why most of the budget for this plan depends on the support of the U.S. government. In Japan because of the Law for the Conservation of Endangered Species of Wild Fauna and Flora countermeasures for conservation and recovery can be taken; however, unfortunately they are nowhere near as good as those in the U.S. in terms of concreteness and legal force, making this somewhere we need follow U.S. policy in the future.

Another lucky thing for the Short-tailed Albatross was the exceptional smoothness of conservation measures as both Torishima Island, a traditional breeding ground for them, and Mukojima Island, where they have been reintroduced, are isolated and thus cause relatively little conflict of interest with industry. With most endangered species there are people and industries that have vested interests in the habitat and coordinating conservation and the interests of local industry and people can be a difficult issue. Much larger efforts than in the case of the albatross are normally very much necessary.

The success of this project depends on whether the chicks can mature and return to Mukojima Island in about 5 years time. According to a preceding experiment, where one month old and 5.5 month old Laysan Albatross chicks were transported to an island 5km from their birthplace of the Midway atoll (Fisher, 1971), 35% of the one month old chicks that successfully matured returned to the island they were transported to three years later, with none returning to their birthplace, while only 5% of the 5.5 month old chicks returned to the island they were transported to three years later. We attempted artificial breeding by transporting approximately one month old chicks that had been born on Torishima Island to the Mukojima islands after taking that previous result into consideration. Earlier transportation to ensure “imprinting” to occur with Mukojima Island would make artificial raising difficult, with this kind of trade-off being a big issue in determining the earliest time to transport them and the method of doing so.

One of the issues with the recovery of the Short-tailed Albatross is how to make their reintroduction to the Mukojima islands successful. Another is the conservation of not only their breeding ground but also their entire environment, which includes oceanic feedingg areas. In particular any sea pollution around the feeding area and fishery by-catches are significant risks to the future of the albatross. Hence first specifying all their feeding areas is essential in averting some of that risks. Japanese and American researchers have commenced researching the feeding areas in both the breeding and non-breeding seasons by tracking them with artificial satellites.

I said that it was lucky for the conservation of the albatross that the breeding site is an isolated island; however, physical strength from the researchers traveling to the site and excellent organization from the entities that will perform the research will be required due to that isolation. The successful nest leaving of 10 chicks that took place is just the beginning of the Mukojima reintroduction plan. We wish to secure the recovery of the albatross by ensuring this plan is successful through the support of our many collaborators who include the Japanese government.

Chinese / French / Japanese