Mergus serrator
Silhouette: Sheatherius · PhyloPic
In 3 days ~10%
The red-breasted merganser (Mergus serrator) is a duck species that is native to much of the temperate to subarctic Northern Hemisphere. The red breast that gives the species its common name is only displayed by males in breeding plumage. Individuals fly rapidly, and feed by diving from the surface to pursue aquatic animals underwater, using serrated bills to capture slippery fish. They migrate each year from breeding sites on lakes and rivers to their mostly coastal wintering areas, making them the most frequent species in the genus Mergus to frequent saltwater regularly. The worldwide population of this species is stable, though it is threatened in some areas by habitat loss and other factors.
The red-breasted merganser was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the current binomial name Mergus serrator. The species is monotypic; no subspecies are recognised. Birds breeding in Greenland were sometimes distinguised as a subspecies M. s. schioleri in the past on the basis of averaging very marginally larger, but this is no longer accepted as distinct.
The genus name Mergus is... Wikipedia →
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Prague Zoo | 🇨🇿 Czechia | |
| 2 | Tierpark Berlin | 🇩🇪 Germany | |
| 3 | Slimbridge Wetland Centre | 🇬🇧 United Kingdom | |
| 4 | Fort Worth Zoo | 🇺🇸 United States | |
| 5 | Santillana Zoo | 🇪🇸 Spain | |
| 6 | Alpenzoo Innsbruck | 🇦🇹 Austria | |
| 7 | Rákosův pavilon | 🇨🇿 Czechia | |
| 8 | Velemlokárium | 🇨🇿 Czechia | |
| 9 | akwarium warszawskiego ZOO | 🇵🇱 Poland |
Rare
Under 5% of wildlife watchers report a Red-breasted Merganser sighting in San Francisco on a given day, based on 1,875 verified sightings from GBIF citizen-science data. It is the 175th most-seen of the 375 birds we can rate there. Over three days the chance rises to about 10%, if each day is a fresh chance.
December
In that month about 10% of wildlife watchers report a Red-breasted Merganser in San Francisco on a given day, against under 5% in January to November, the lowest months. That is one of San Francisco's wettest months, with about 110 mm of rain against almost none in July.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Red-breasted Merganser sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
28th of 57
Of the 57 cities where we can rate Red-breasted Merganser sightings, San Francisco ranks 28th at under 5%. The best odds are in Sendai (Japan, about 20%), Toronto (Canada, about 20%) and Dalian (China, about 20%).
GBIF citizen-science records
It is estimated from how often the Red-breasted Merganser is recorded against all the birds logged in San Francisco (1,875 verified sightings), 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.
