A second group of Nihoa millerbirds has been successfully
moved from Nihoa to Laysan—both islands in the northwestern end of the Hawaiian
archipelago.
The movement assures the species of a second breeding
population, improving its potential for survival.
(Image: Millerbirds handed down the slope of rocky Nihoa
Island. Credit: USFWS.)
Biologists collected, shipped by boat from Nihoa to Laysan,
and released 26 millerbirds in mid-August, in a joint effort of the U.S. Fish
and Wildlife Service (FWS), American Bird Conservancy (ABC), and other
organizations. Twenty-four millerbirds were moved to the island in 2011, and
those first birds have already produced 17 chicks.
“So far, everything has gone extremely well for the birds,”
said millerbird expert and University of Hawai`i biologist Sheila Conant. “They
were captured without incident; they made it through the boat ride in good
health; we had no problems attaching transmitters to them; and they have now
been released to their new habitat without a hitch. So we are thrilled with the way this phase
has gone.”
(Image: Photographer captures the release of millerbirds in
the green fields of flat Laysan Island. Credit: Sheldon Plentovich, USFWS.)
Millerbirds eat insects. The little (one-ounce) birds forage
in the low shrubs and bunchgrasses of the islands. They are relatives of a
class of birds known as old world warblers. BirdLife International has more information here.
This species is not new to Laysan. A subspecies, the Laysan
millerbird, existed on Laysan until introduced rabbits helped denude the island
of much of its vegetation, and the habitat destruction killed off the birds.
Laysan’s rabbits have long since been removed and the native vegetation is
being restored.
(Image: A millerbird on Laysan with a fresh spider in its
bill. Credit, John Vetter, USFWS.)
Scientists are assuming that the 50 birds translocated in
the 2011 and 2012 projects will provide a sufficient founder population to
allow a healthy self-sustaining population to develop, said Don Palawski,
Acting Fish and Wildlife Service Superintendent of the Papahānaumokuākea Marine
National Monument, which encompasses the Northwestern Hawaiian Islands.
Work during the first year of Nihoa millerbird presence on
Laysan suggests that the habitat is appropriate for them, and there is
sufficient food.
Laysan is an extremely isolated island, without an airfield
or harbor. Researchers arrive at the island on small boats from research
vessels anchored offshore. Winter access is generally not possible due to surf,
but one researcher will remain on the island through the winter season to keep
tabs on the birds.
The Fish and Wildlife Service web page on its millerbirdwork is here.
© Jan TenBruggencate 2012
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