Laysan albatross have only two main nesting sites

ON THE FACE of things, the Laysan albatross is doing fairly well. Its population is estimated at around 1.6m, and may be growing. The International Union for Conservation of Nature (IUCN) classifies it as “near-threatened”, putting it on the second rung from the bottom of the organisation’s seven-rung ladder to extinction. A cause for moderate concern. But not, you may think, something that should be top of conservationists’ lists of priorities. However, like another reasonably abundant migratory species, the monarch butterfly, the Laysan albatross has an Achilles heel.

Though monarchs range across much of North America, many are, or are the descendants of, insects that have roosted over winter in the same few groves of trees in central Mexico. Destroy those trees and you would imperil the species. The Laysan albatross has a similar vulnerability. Adult birds traverse much of the Pacific Ocean. But more than 90% of them started life on one of two specks of land, Midway and the eponymous Laysan, which are among the most north-westerly members of the Hawaiian archipelago. Wipe out those breeding colonies and the Laysan albatross would shoot right up the IUCN ladder.