Larus marinus
Silhouette: Andy Wilson · PhyloPic
In 3 days <5% in a week ~10%
The great black-backed gull (Larus marinus) is the largest member of the gull and tern family Laridae. It is a very aggressive hunter, pirate and scavenger which breeds on the North Atlantic coasts and islands of northern Europe and northeastern North America. Southern populations are generally sedentary, while those breeding in the far north (northern Norway, northwest Russia) migrate farther south in winter. A few also move inland to large lakes and reservoirs. The adult has a white head, neck and underparts, dark blackish-grey wings and back, pink legs and the bill yellow with a red spot.
The great black-backed gull was one of the many species originally described by Carl Linnaeus in his 1758 10th edition of Systema Naturae, and it still bears its original scientific name of Larus marinus. Larus appears to have referred to a gull or other large seabird. The specific name marinus means "marine", or when taken together, "sea gull". The name predates Linnean taxonomy, as it had been called Larus ingens marinus by Carolus Clusius.
The terms swaabie (from Norn: swartbak, lit. 'black back'), baagie and baigie (Norn: bagi, from Old Norse: bak, lit. 'back') are local names... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cape Breton Highlands National Park | 🇨🇦 Canada | |
| 2 | Gros Morne National Park | 🇨🇦 Canada | |
| 3 | Acadia National Park | 🇺🇸 United States | |
| 4 | Wadden Sea National Park | 🇩🇪 Germany | |
| 5 | Snowdonia National Park | 🇬🇧 United Kingdom | |
| 6 | Vatnajokull National Park | 🇮🇸 Iceland | |
| 7 | Point Pelee National Park | 🇨🇦 Canada | |
| 8 | Merritt Island National Wildlife Refuge | 🇺🇸 United States | |
| 9 | Svalbard | 🇳🇴 Norway | |
| 10 | Cairngorms National Park | 🇬🇧 United Kingdom | |
| 11 | Everglades National Park | 🇺🇸 United States | |
| 12 | Doñana National Park | 🇪🇸 Spain |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Liverpool | 🇬🇧 United Kingdom | |
| 2 | Dublin | 🇮🇪 Ireland | |
| 3 | Helsinki | 🇫🇮 Finland | |
| 4 | New York City | 🇺🇸 United States | |
| 5 | Montreal | 🇨🇦 Canada | |
| 6 | Boston | 🇺🇸 United States | |
| 7 | Copenhagen | 🇩🇰 Denmark | |
| 8 | Baltimore | 🇺🇸 United States | |
| 9 | Rotterdam [The Hague] | 🇳🇱 Netherlands | |
| 10 | Stockholm | 🇸🇪 Sweden |
Rare
Under 5% of wildlife watchers report a Great Black-backed Gull sighting in Everglades National Park on a given day, based on 70 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 209th most-seen of the 273 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.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Great Black-backed Gull in Everglades National Park on a given day, so our monthly data shows no clear season.
Between 3 and 6 pm
Across all the parks we cover, that three-hour window holds the most Great Black-backed Gull sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
11th of 12
Of the 12 parks where we can rate Great Black-backed Gull sightings, Everglades National Park ranks 11th at under 5%. The best odds are in Cape Breton Highlands National Park (Canada, about 50%), Gros Morne National Park (Canada, about 50%) and Acadia National Park (United States, about 40%). All parks ranked.
GBIF citizen-science records
It is estimated from how often the Great Black-backed Gull is recorded against all the birds logged in Everglades National Park (70 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.
