Endangered Hawaiian geese have been seen in the wild on Oahu for the first time in centuries, indicating the chances of survival for the native birds are improving, federal and state officials said.
A pair of nene that migrated to Oahu has nested and hatched three goslings at the James Campbell National Wildlife Refuge in Kahuku, the U.S. Fish and Wildlife Service announced Monday.
"Any time you get a new population like that started, it decreases the overall probability of extinction of the species," said Steve Hess, a U.S. Geological Survey wildlife biologist.
It is the first time Hawaii’s official state bird has been sighted in the wild on Oahu since the 1700s, officials said.
The nene population was estimated at 25,000 in the 1800s but by the 1950s had dwindled to about 30, according to state research. The statewide population has increased from an estimated 1,500 in 2005 to more than 2,000.
Authorities have been flying nene from Kauai, where the population has been growing rapidly, to Maui and Hawaii island by helicopter and Coast Guard plane to establish more populations on those islands.
State Division of Forestry and Wildlife manager David Smith said the chances of survival increase by transplanting the nene to different islands — establishing more than one nesting population in case something happens to one on a single island.
"Ultimately, you want to spread out the population as much as possible," Smith said.
The state has not chosen Oahu as a nene habitat because of the its dense population.
According to the banding on the legs, the birds that have migrated here were originally from Hawaii island, Smith said.
Scientists have learned that nene tend to travel.
One group released in West Maui was found 20 miles away on Haleakala and has been seen flying in a V formation above the southern rim of the volcano.
They’re known to cross Hawaii island in a day — so it’s not surprising that they would fly to Oahu, Hess said.
"But the fact that they would stop and raise youngsters over there — that’s pretty remarkable," said Hess, who has studied nene but is not involved with the geese on Oahu.
Scientists believe nene are descendants of Canada geese that flew here nearly 1 million years ago.
They lost habitat to agriculture after Polynesians arrived in Hawaii about 1,000 years ago. When the first Europeans landed in 1778, the birds were only known to live on Hawaii island. Fossilized remains of nene, however, have been found on Oahu and most of the other main Hawaiian Islands.
Unrestricted hunting after Europeans arrived took out even more of the birds.
They eat a variety of plants and are attracted to golf courses where they can feed on short grass with high nutritional content, according to wildlife officials.
And they can be territorial and temperamental, in at least one instance chasing golfers from greens on a course on Maui. A fence was built around the 18th green at the Maui Lani Golf Course in Kahului to prevent a nesting gander from chasing players.
The Hawaiian goose, Branta sandvicensis, grows as tall as 23 to 28 inches and weights between four and five pounds.
With its scattered wetlands, the James Campbell National Wildlife Refuge was established as a U.S. Fish and Wildlife area in 1976 to provide habitat for endangered waterbirds, including the Hawaiian stilt and Hawaiian coot.
Government officials have developed predator-control programs to protect endangered waterbirds against mongooses, feral dogs, cats, pigs, bullfrogs and cattle egrets.
Authorities have scheduled a news conference for Wednesday about the nene that have taken up residence in Kahuku.
The Associated Press contributed to this report.
