Contacts
Barbara Maxfield, 808 792 9530 or 753 0440
Biologists were surprised last year when endangered Laysan ducks that had been translocated to Midway Atoll National Wildlife Refuge only six months earlier began to breed. Even more surprising now is that the ducklings born just last year on Midway are already nesting, and the first of Midway's second generation ducklings hatched Sunday.
"We did not expect the second generation of ducklings so soon," said U.S. Geological Survey scientist Dr. Michelle Reynolds, the project leader for the Laysan duck reintroduction program. "It is a very encouraging sign that the Midway population is increasing naturally since the translocation of the wild birds from Laysan."
Eleven first-generation ducklings survived last year, and two of these nested. Despite heavy rains on Sunday morning, eggs from both nests hatched. One female has 4 ducklings and the other 1 duckling. At least 25 ducklings borne to 8 mother ducks have hatched so far this year, and 5 additional hens are incubating eggs. Forty of the 42 founding birds from Laysan have survived to date. Excluding ducklings, Midway has 35 Laysan ducks on Sand Island and 16 on Eastern Island.
Breeding and survival of the birds is being monitored closely by biologists using radio telemetry. Researchers have observed interesting differences in reproductive effort between the source and translocation populations. The translocated ducks are breeding at an earlier age, and are laying more eggs than ducks observed on Laysan Island, suggesting that the food or habitat on Laysan has reached the limits of its ability to support more ducks. In contrast, Midway Atoll, with its relatively low density duck population, has abundant habitat and abundant food resources available, possibly stimulating early reproductive effort.
The endangered Laysan duck (Anas laysanesis), also known as the Laysan teal, is the rarest native waterfowl in the United States. The island ducks were once widespread across the Hawaiian Islands, but by 1857, they only remained on Laysan Island. In October 2004 and 2005, 42 wild Laysan ducks were experimentally translocated from Laysan Island to Midway Atoll.
"The breeding success of the new population at Midway Atoll is like a reward for everyone involved in the project," said refuge biologist John Klavitter. In preparation for the arrival of the ducks, Midway refuge staff and more than 80 volunteers invested more than 20,000 hours in habitat restoration work over 2 years. After removing hundreds of thousands of invasive plants, shallow freshwater seeps were excavated, and hundreds of bunchgrasses, sedges, and other native vegetation were planted to provide cover, forage, and nesting habitat.
Island ducks are endangered worldwide, but the re-establishment of a second or "insurance" population at Midway Atoll reduces this species? risk of extinction from a catastrophe striking Laysan Island, part of the Hawaiian Islands National Wildlife Refuge. The effects of a hurricane, tsunami, new diseases (like avian flu), or the accidental introductions of harmful plants and animals could easily have caused the extinction of Laysan ducks since they occurred as a single population. Laysan ducks are now found on three islands for the first time in hundreds of years.
In recent years, translocation has emerged as a key conservation tool in the recovery of endangered species in Hawai'i and elsewhere. It has been especially useful for restoring species to islands, or habitat islands (like volcanoes, or forest kipukas - isolated forests surrounded by young lava flows), where they formerly occurred or to locations where introduced predators and competitors are absent. Populations transferred to islands are easier to monitor and manage than are populations reintroduced to larger landmasses. The palila, a Big Island honeycreeper, was recently experimentally translocated from its last remaining wild population on western Mauna Kea to the northern slope of the same volcano.
The Laysan duck was listed as endangered in 1966 because of its small population (~500 birds), small geographic range (less than 4 sq. mi), and dependence upon a fragile ecosystem. The effort to establish a second population on Midway Atoll NWR has been a collaborative effort led by the U.S. Geological Survey?s Pacific Island Ecosystems Research Center and the U.S. Fish and Wildlife Service. This collaborative effort is a model for application of research for species recovery, and should provide excellent information for how to further increase the population and distribution of this island- isolated endangered species. The nonprofit groups National Fish and Wildlife Foundation, Friends of Midway Atoll, and the U.K.'s Wildfowl and Wetland Trust have provided grants and support to help save the Laysan duck.
The U.S. Fish and Wildlife Service is the principal Federal agency responsible for conserving, protecting and enhancing fish, wildlife and plants and their habitats for the continuing benefit of the American people. The Service manages the nearly 100-million-acre National Wildlife Refuge System, which encompasses 545 national wildlife refuges, thousands of small wetlands and other special management areas. It also operates 69 national fish hatcheries, 64 fishery resources offices and 81 ecological services field stations. The agency enforces federal wildlife laws, administers the Endangered Species Act, manages migratory bird populations, restores nationally significant fisheries, conserves and restores wildlife habitat such as wetlands, and helps foreign and Native American tribal governments with their conservation efforts. It also oversees the Federal Assistance program, which distributes hundreds of millions of dollars in excise taxes on fishing and hunting equipment to state fish and wildlife agencies.
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