Saturday, June 25, 2011

Short-tailed Albatross Fledges

Short-tailed Albatross / USFWS Photo
The first Short-tailed Albatross born outside of Japan fledged this week on Eastern Island in Midway Atoll NWR.
The hatchling broke through its shell in January on Eastern Island, one of three small, flat, coral islands that comprise Midway Atoll National Wildlife Refuge over 1,300 miles northwest of Honolulu. The parents of the Midway chick first paired up on the refuge four years ago. During that 2007-8 breeding season, they were observed spending only a little time together, but the following season, their time together increased. By the third season, they arrived at the Eastern Island breeding colony together and built a nest, but did not lay eggs. This breeding season, one of the pair was observed incubating a freshly laid egg on November 16, 2010. The pair has been under close observation ever since. The U.S. Fish and Wildlife Service (FWS) reports that the birds’ leg bands reveal that the male of the pair was hatched on the island of Torishima, Japan in 1987, while the female hatched there in 2003.

After the egg hatched in January, the parents spent the next five months bringing squid and flying fish to their chick every one to three days. In doing so, they logged tens of thousands of miles, likely soaring between Midway and the nutrient-rich feeding grounds some 1,000 miles to the northwest. While the parents were both away on one foraging trip, the chick was swept off its nest by the tsunami resulting from the catastrophic Japanese earthquake of 11 March.  It survived the ordeal, and in May, after months of steady feeding and growth, had lost most of its downy look and begun stretching and exercising its wings.

Anticipating its fledging, the chick was banded by FWS biologists on June 8. It has now left the island and is most likely headed in a northwesterly direction to the rich and productive waters near Hokkaido, Japan. On average, Short-tailed Albatrosses begin breeding at 6 years of age, but often begin prospecting at nesting sites several years earlier. So, it is our hope that this bird return in 4-6 years, and it could begin breeding by about 2017, provided it finds a mate.
Hopefully it will be the first of many Short-tailed Albatrosses to fledge on Eastern Island. The refuge is already home to the world's largest population of Laysan Albatrosses. This makes it a natural site to establish an alternate breeding location for an endangered albatross.
The endangered Short-tailed Albatross was once the most abundant of the North Pacific albatross species, numbering more than a million birds. It was decimated by feather hunting at the turn of the 20th Century, and by the late 1940s was thought to be extinct. In the early 1950s, ten pairs were discovered breeding on Torishima. The population has now reached 3,000 individuals, with some birds on the Senkaku Islands, but most still on Torishima.

Conservationists fear an eruption of the active volcano on Torishima could spell disaster. Starting in 2008, an international team led by Japan’s Yamashina Institute began translocating Short-tailed Albatross chicks to Mukojima Island to create a new “insurance” population. In 2011, 15 chicks were moved to Mukojima, bringing the total number translocated to 55. So far, seven of these birds have returned to Mukojima as non-breeding juveniles, an encouraging sign that they will return to breed when they reach maturity. Outside the breeding season, the Short-tailed Albatross ranges along the coasts of eastern Russia, Korea, China, Taiwan, and Alaska and the Hawaiian Islands, and occasionally off the Pacific Coast of North America.
It will be interesting to see if this is the start of a larger colony.