Millerbird singing. Photo by Robby Kohley

Decades of conservation work led by the U.S. Fish and Wildlife Service (USFWS) and supported by American Bird Conservancy (ABC) and partners has paid off for Hawai‘i’s Millerbird (Ulūlu). Today, the International Union for Conservation of Nature (IUCN) Red List of Threatened Species announced that the species is being downlisted to Endangered status after being listed as Critically Endangered since 2000. Once found only on the island of Nihoa, a team of scientists and conservationists translocated 50 individuals to Laysan, creating a second, self-sustaining population that significantly decreased this species’ risk of extinction.

“The Millerbird translocations were an exciting, collaborative victory for Hawaiian conservation and it is immensely rewarding seeing this recognized by IUCN,” said Chris Farmer, ABC’s Hawai‘i Program Director, who participated in the translocations. “The population increase on Laysan will help protect this species’ future, and shows that long-term support and commitment can prevent extinctions of any other Hawaiian birds.”

The Millerbird, a small insect-eating warbler, was once found on both Nihoa and Laysan (Kauō) Islands in the Northwestern Hawaiian Islands. Tragically the population on Laysan went extinct by the early 20th century, along with two other endemic bird species, the Laysan Rail and Laysan Honeycreeper, due to loss of vegetation from nonnative rabbits and other introduced mammals. After that, the species was limited to a few hundred individuals on the rocky, 178-acre Nihoa, 650 miles away from Laysan.

To prevent another extinction from happening, a goal was set to establish a second “insurance” population of Millerbirds on Laysan. Rabbits and other invasive mammals were removed from Laysan by 1923. After years of natural regeneration and intensive habitat restoration by USFWS, the island had recovered sufficiently to make it suitable for the Millerbird reintroduction effort.

In a great conservation success story, a total of 50 Millerbirds were translocated to Laysan from Nihoa in 2011 and 2012 by ABC, USFWS, and other partners. At 1,023 acres, Laysan is the second largest of the Northwestern Hawaiian Islands and is located in the Papahānaumokuākea Marine National Monument (PMNM), one of the largest environmentally protected marine areas in the world. Experts estimate that several hundred Millerbirds inhabit Laysan today, and they have expanded into all the vegetated parts of the island. 

The first translocation of 24 Millerbirds took place in September 2011 after years of research and preparation, followed by a second translocation of 26 birds the year after. Working with PMNM’s Native Hawaiian Cultural Working Group, the translocated population received the name Ulūlu niau.  

To understand the fate of the translocated birds, their movements, and breeding activity, birds were marked with a unique set of color bands on their legs, making it easier to track individuals. Research entailed tracking a subset of the birds with temporary radio transmitters, nest monitoring, and re-sighting color-banded birds as frequently as possible. This was not an easy task due to Millerbirds’ secretive nature in the dense, bushy habitat they frequent on Laysan.

“The year 2023 is the centennial of the extinction of the Laysan subspecies of Millerbird. It’s remarkable to think that exactly 100 years later, the Millerbird is now being downlisted, because Millerbirds are once again flourishing on Laysan,” said George Wallace, former Vice President for Oceans and Islands and now a volunteer Ambassador at ABC. “It’s rewarding seeing these birds thrive, not only because they have been a missing piece of the island’s native ecosystem for so long, but also because this marks a turning point in the recovery of the species.” Wallace was a member of the Millerbird translocation team.

The Millerbird isn’t the only endangered species benefiting from the conservation efforts on Laysan. The Laysan Finch (‘Ekupu‘u), Laysan Duck, and several plant species, along with millions of nesting seabirds such as Laysan Albatross (Mōlī) and Black-footed Albatross (Ka‘upu) continue to do well.

While the work to restore Laysan and recover the Millerbird are beacons of success, it is sobering to note that, once a bird paradise, Hawai‘i is now the bird extinction capital of the world with many species on the brink and more at risk of disappearing in our lifetime. Since human settlement of the islands, 95 of 142 bird species found nowhere else have become extinct in Hawai‘i. Twenty-six of Hawai‘i’s remaining 37 endemic birds are listed under the Endangered Species Act. Three of these have not been seen in decades, and an additional eight were recently declared extinct

The remaining birds face multiple threats, ranging from loss of their unique feeding and nesting areas to direct predation by invasive species, and avian malaria and pox transmitted by non-native mosquitoes, diseases which have decimated populations of Hawaiian birds.

While some have given up on Hawai‘i as a lost cause, ABC stands firm and maintains its long-term commitment to prevent the extinctions of native Hawaiian birds.

ABC is grateful for the opportunity to partner with USFWSNational Fish and Wildlife FoundationPacific Bird ConservationPapahānaumokuākea Marine National MonumentPacific Rim ConservationUniversity of Hawai‘iUniversity of New BrunswickU.S. Geological Survey National Wildlife Health Research Center, and Office of Hawaiian Affairs to make the Millerbird project possible.

For more information, visit ABC’s Millerbird Project and ABC’s Hawai‘i Program.

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