Ka Wai Ola - Office of Hawaiian Affairs, Volume 26, Number 9, 1 September 2009 — Cautionary tale emerges from Laysan Duck die-off [ARTICLE]

Cautionary tale emerges from Laysan Duck die-off

Scientists report that an effort to rebuild the population of Laysan Ducks, one of the world's most endangered waterfowl species, nahve onfy to Laysan Island in the Northwestern Hawaiian Islands, has hit a snag. In a project begun hve years ago, biologists released 42 Laysan Ducks on Midway Atoll, one day's boat ride from Laysan. By 2007, the population grew to 200 ducks. However, in August 2008, 181 of the ducks on Midway died in a disease epidemic lasting 30 days. Necropsies revealed botulism type C as the cause of death. Dr. Thierry Work of the U.S. Geological Survey said in a news release that three of the ducks were also infected with a worm that has been responsible for mass die-offs of Laysan Ducks on tiny Laysan Island.

He said monitoring the wetland enviromnent and the birds for early disease detection and management will be needed to offset any potential harm. Although it is unclear whether the worms arrived with migratory waterfowl or were introduced during translocations, Thierry said the dieoff highlights the risks associated with managing newly translocated endangered species. He said the disease risks resulting from translocations are important to understand now that climate change is altering the habitat range of endangered species, leading wildlife biologists to look at translocation as a solution to maintaining populahon levels.