Anas wyvilliana
In 3 days ~10% in a week ~20%
The Hawaiian duck (Anas wyvilliana) or koloa is a species of bird in the family Anatidae that is endemic to the large islands of Hawaiʻi. Taxonomically, the koloa is closely allied with the mallard (A. platyrhynchos). It differs in that it is monomorphic (with similarly marked males and females) and non-migratory. As with many duck species in the genus Anas, Hawaiian duck and mallards can interbreed and produce viable offspring, and the koloa has previously been considered an island subspecies of the mallard. However, all major authorities now consider this form to be a distinct species within the mallard complex. Recent analyses indicate that this is a distinct species that arose through ancient hybridization between mallard and the Laysan duck (Anas laysanensis). The native Hawaiian name for this duck is koloa maoli (meaning "native duck"), or simply koloa. This species is listed as vulnerable by the IUCN Red List of Threatened Species, and its population trend is increasing.
Both male and female are mottled brown in color and resemble a female mallard. The males are usually bigger than the females, and have a darker head and neck. The female is generally...
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Kilauea Point National Wildlife Refuge | 🇺🇸 United States |
More parks will be added in future updates.
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Copenhagen Zoo | 🇩🇰 Denmark | |
| 2 | Waikiki Aquarium | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Hawaiian Duck sighting in Kilauea Point National Wildlife Refuge on a given day, based on 35 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 26th most-seen of the 44 birds we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
September and November
In those months about 10% of wildlife watchers report a Hawaiian Duck in Kilauea Point National Wildlife Refuge on a given day, against under 5% in October and December–August, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Hawaiian Duck sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Kilauea Point National Wildlife Refuge, in our data
Kilauea Point National Wildlife Refuge is the only park on Wallace's Line with enough records to rate Hawaiian Duck sightings: under 5% of wildlife watchers there report one on a given day.
GBIF citizen-science records
It is estimated from how often the Hawaiian Duck is recorded against all the birds logged in Kilauea Point National Wildlife Refuge (35 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
