Critically Endangered
Laysan Duck
Anas laysanensis
The Laysan duck, also known as the Laysan teal, and sometimes known by its Hawaiian name, koloa pōhaka, is a dabbling duck endemic to the Hawaiian Islands.
Appearance
The Laysan duck is teal-sized and dark brown, with a prominent white eye-ring. The bill is short and spatulate, dark green with variable black blotching in males, and dull orange with variable black blotching in females. Some males show faint iridescence on the head or neck and have slightly upturned central tail feathers.
Range and habitat
The Laysan duck, also known as the Laysan teal, and sometimes known by its Hawaiian name, koloa pōhaka, is a dabbling duck endemic to the Hawaiian Islands. Fossil evidence reveals that Laysan ducks once lived across the entire archipelago, but today survive only on Laysan Island and two atolls. The duck has several physical and behavioral traits linked to the absence of ground-based predators in its habitat.
By 1860, the ducks had disappeared from everywhere except Laysan Island. Rabbits were eradicated from the island in 1923 and numbers of Laysan ducks began to rise, reaching 500 by the 1950s.
Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.
Diet and breeding
The Laysan duck is a poor flyer, but walks and runs well, with a pelvic girdle adapted to terrestrial foraging. Energetic foraging behavior includes a fly-snapping sprint through Neoscatella sexnotata brine fly swarms.
The ducks also will dabble and filter feed along lake shallows, shore, and in upland vegetation for macroinvertebrates, algae, leaves, and seeds. During the day, and especially in the breeding season, they prefer to hide among the grass and shrub vegetation, helping them to avoid avian predators such as frigatebirds. Pair formation begins in autumn, and nest building begins in spring.
In crisis
The introduction of European rabbits by guano miners at the end of the 19th century brought the bird to the brink of extinction in 1912, with twelve surviving individuals. After many domestic rabbits starved and the remaining ones were eradicated by biologists in 1923, the ducks began to recover, increasing to a population of about 500 individuals by the 1950s. Even so, population bottlenecks occurred, such as the severe 1993 El Niño drought and food shortage, that reduced the number of ducks to about 100.
In 2004, the population grew to an estimated 576 ducks. In October 2004 and 2005, 42 Laysan ducks were translocated to Midway Atoll National Wildlife Refuge as a collaborative effort between the United States Geological Survey and Fish and Wildlife Service to establish a second population of ducks in the wild.
CITES lists this taxon on Appendix I. Confirm the current appendix on the CITES checklist.
Laysan Duck is Critically Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.
Sources
Written for this catalog from the English Wikipedia article on Laysan Duck, Wikidata item Q247745. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.
