An endangered short-tailed albatross has laid an egg for the first time at Midway Atoll, the U.S. Fish and Wildlife Service has announced.

If the egg hatches in the middle of next month, the island might become the third breeding ground for the birds, joining Japan’s Torishima island, part of the Izu Islands, and the Senkaku Islands.

The nest is on Midway’s Eastern Island, about 1,370 miles northwest of Honolulu. Off-limits to the general public, it is administered by the wildlife service as a nature reserve.

The mother and father bird have been taking turns warming the egg. Their leg rings show both birds were born on Torishima island, and that the male left his birth nest in 1987 and the female left hers in 2003.

The Oceanic Wildlife Society, a Japanese nonprofit organization that protects mainly marine wildlife, and other entities placed 16 decoys on Midway Atoll in 2000 to help the birds form a new colony.

Environmentalists have been trying to get the albatrosses there to form pairs by putting out the elaborately made models of the birds, and playing bird cries recorded on Torishima island.

Short-tailed albatrosses were once thought to have become extinct between the late 19th and early 20th centuries, as a result of overhunting for their feathers. However, in 1951, the birds were confirmed to be breeding on Torishima island and efforts have been made to protect them ever since. Although their numbers are gradually increasing, the birds’ population is still estimated at only about 3,000.

“There’s friction between Japan and China over the Senkaku Islands and a danger of volcanic eruptions on Torishima island,” said OWS Chairman and Toho University Professor Hiroshi Hasegawa, who has worked to protect the albatross on Torishima island.

“If Midway Atoll, which is made of coral reefs, becomes a new breeding ground for the birds, it would be a significant help to ensuring their survival,” he said.

The Environment Ministry has been working to create a new breeding ground for the birds by transferring chicks from Torishima island to Mukojima island, part of the Ogasawara Islands, since 2008.