Mergellus albellus
Silhouette: Sheatherius · PhyloPic
In 3 days <5% in a week ~10%
The smew (Mergellus albellus) is a species of duck and is the only living member of the genus Mergellus. The genus is closely related to Mergus and is sometimes included in it; genetic studies have shown that it is the sister taxon to Mergus and Lophodytes. The smew has hybridised with the common goldeneye (Bucephala clangula).
The smew was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the binomial name Mergus albellus. Linnaeus based his account on the description published in 1757 by another Swedish naturalist, Fredrik Hasselqvist, who collected one in Smyrna (now İzmir) in Turkey. Linnaeus specified the type locality as Europe but this was restricted to the Mediterranean near İzmir in Turkey on the basis of Hasselqvist's travels. The smew is now the only living species placed in the genus Mergellus that was introduced in 1840 by the English naturalist Prideaux Selby. The species is monotypic, with no subspecies recognised.
The genus name Mergellus is a diminutive of Mergus, a Latin word related to mergo, to dive or submerge, used by Pliny for an unspecified diving bird. The specific... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Biebrza National Park | 🇵🇱 Poland | |
| 2 | Wadden Sea National Park | 🇩🇪 Germany | |
| 3 | Kiskunság National Park | 🇭🇺 Hungary | |
| 4 | Hortobágy National Park | 🇭🇺 Hungary | |
| 5 | Białowieża National Park | 🇵🇱 Poland | |
| 6 | Bavarian Forest National Park | 🇩🇪 Germany |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Helsinki | 🇫🇮 Finland | |
| 2 | Beijing | 🇨🇳 China | |
| 3 | Nizhny Novgorod | 🇷🇺 Russia | |
| 4 | Daejeon | 🇰🇷 South Korea | |
| 5 | Osaka | 🇯🇵 Japan | |
| 6 | Birmingham | 🇬🇧 United Kingdom | |
| 7 | Nagoya | 🇯🇵 Japan | |
| 8 | Busan | 🇰🇷 South Korea | |
| 9 | Seoul | 🇰🇷 South Korea | |
| 10 | Copenhagen | 🇩🇰 Denmark |
Rare
Under 5% of wildlife watchers report a Smew sighting in Białowieża National Park on a given day, based on 9 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 165th most-seen of the 182 birds we can rate there. Over three days the chance rises to under 5%, and over a week to about 10%, if each day is a fresh chance.
March
In that month about 10% of wildlife watchers report a Smew in Białowieża National Park on a given day, against under 5% in April to February, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Smew sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 6 parks where we can rate Smew sightings, Białowieża National Park ranks 5th at under 5%, level with the leaders once rounded. The best odds are in Biebrza National Park (Poland, under 5%), Wadden Sea National Park (Germany, under 5%) and Kiskunság National Park (Hungary, under 5%).
Same family: Anatidae
The closest relatives of the Smew that you can see in Białowieża National Park (family Anatidae, Ducks, Geese, and Swans) are Mallard (about 50%), Greylag Goose (about 20%) and Mute Swan (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Smew is recorded against all the birds logged in Białowieża National Park (9 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.
