Larus brachyrhynchus
Silhouette: Sharon Wegner-Larsen · PhyloPic
In 3 days ~20% in a week ~40%
The short-billed gull (Larus brachyrhynchus) is a species of gull that breeds in northwestern North America. In North America, it was previously known as the mew gull, when it was considered conspecific with the palearctic common gull (Larus canus). Most authorities, including the American Ornithological Society in 2021, have split the two populations as distinct species.
The species was first described by Scottish naturalist John Richardson in 1831 as the 'short-billed mew gull', Larus brachyrhynchus. Though some authorities, including the American Ornithologist's Union from 1931 onwards, have long considered brachyrhynchus to be a subspecies of the common gull, others have recognized the two as distinct species. In 2021, the American Ornithological Society agreed to split the short-billed gull as a distinct species based on differences in genetics, plumage, morphology and vocalizations. Though 'mew gull' has been used as name for the species in North America, the name short-billed gull was chosen due to the usage of "mew gull" in recent literature to denote all forms of L. canus and the fact that short-billed gull was previously used in older AOS checklists since... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Katmai National Park | 🇺🇸 United States | |
| 2 | Denali National Park | 🇺🇸 United States | |
| 3 | Great Bear Rainforest | 🇨🇦 Canada | |
| 4 | Kluane National Park | 🇨🇦 Canada | |
| 5 | Pacific Rim National Park Reserve | 🇨🇦 Canada | |
| 6 | Kenai Fjords National Park | 🇺🇸 United States | |
| 7 | Wrangell-St. Elias National Park | 🇺🇸 United States | |
| 8 | Redwood National Park | 🇺🇸 United States | |
| 9 | Wood Buffalo National Park | 🇨🇦 Canada | |
| 10 | Olympic National Park | 🇺🇸 United States | |
| 11 | Channel Islands National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Anchorage | 🇺🇸 United States | |
| 2 | Seattle | 🇺🇸 United States | |
| 3 | Vancouver | 🇨🇦 Canada | |
| 4 | San Francisco | 🇺🇸 United States | |
| 5 | Portland | 🇺🇸 United States | |
| 6 | Los Angeles | 🇺🇸 United States | |
| 7 | Calgary | 🇨🇦 Canada | |
| 8 | Sacramento | 🇺🇸 United States | |
| 9 | Edmonton | 🇨🇦 Canada | |
| 10 | San Diego | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Short-billed Gull sighting in San Francisco on a given day, based on 6,379 verified sightings from GBIF citizen-science data. It is the 113th most-seen of the 375 birds we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
November to March
In those months about 10% of wildlife watchers report a Short-billed Gull in San Francisco on a given day, against under 5% in April to October, the lowest months. Those are among San Francisco's wettest months, with about 85 mm of rain a month against almost none in July.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Short-billed Gull sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
4th of 11
Of the 11 cities where we can rate Short-billed Gull sightings, San Francisco ranks 4th at about 10%. The best odds are in Anchorage (United States, about 70%), Seattle (United States, about 10%) and Vancouver (Canada, about 10%).
Same genus: Larus
The closest relatives of the Short-billed Gull that you can see in San Francisco (genus Larus, Large White-headed Gulls) are California Gull (about 40%), Western Gull (about 30%) and Ring-billed Gull (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Short-billed Gull is recorded against all the birds logged in San Francisco (6,379 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.
