Thalasseus sandvicensis
Silhouette: JJ Harrison (vectorized by T. Michael Keesey) · PhyloPic
In 3 days ~30% in a week ~50%
The Sandwich tern (Thalasseus sandvicensis) is a tern in the family Laridae. It is very closely related to the lesser crested tern (T. bengalensis), Chinese crested tern (T. bernsteini), Cabot's tern (T. acuflavidus), and elegant tern (T. elegans) and has been known to interbreed with both elegant and lesser crested terns. It breeds in the Palearctic from Europe to the Caspian Sea, and winters in the Mediterranean and on the coasts of Africa, India, and Sri Lanka.
The Sandwich tern is a medium-large tern with pale silvery-grey upperparts, white underparts, a yellow-tipped black bill, and a shaggy black crest which becomes less extensive in winter with a white crown. Young birds bear grey and blackish scalloped plumage on their backs and wings. It is a vocal bird. It nests in a ground scrape and lays one to three eggs.
Like all Thalasseus terns, the Sandwich tern feeds by plunge-diving for fish, usually in marine environments, and the offering of fish by the male to the female is part of the courtship display. The terns are small to medium-sized seabirds, gull-like in appearance, but usually with a more delicate, lighter build and shorter, weaker legs. They have long,... Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Dakar | 🇸🇳 Senegal | |
| 2 | Algiers | 🇩🇿 Algeria | |
| 3 | Rabat | 🇲🇦 Morocco | |
| 4 | Havana | 🇨🇺 Cuba | |
| 5 | Vitória | 🇧🇷 Brazil | |
| 6 | Kuwait City | 🇰🇼 Kuwait | |
| 7 | Casablanca | 🇲🇦 Morocco | |
| 8 | Liverpool | 🇬🇧 United Kingdom | |
| 9 | Porto | 🇵🇹 Portugal | |
| 10 | Dublin | 🇮🇪 Ireland |
With luck
About 10% of wildlife watchers report a Sandwich Tern sighting in Las Baulas Marine National Park on a given day, based on 103 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 75th most-seen of the 206 birds we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
January
In that month about 20% of wildlife watchers report a Sandwich Tern in Las Baulas Marine National Park on a given day, against under 5% in May–June and August–October, the lowest months. That is one of Las Baulas Marine National Park's driest months, with about 10 mm of rain against 480 mm in October.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Sandwich Tern sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
8th of 43
Of the 43 parks where we can rate Sandwich Tern sightings, Las Baulas Marine National Park ranks 8th at about 10%. The best odds are in Ría Lagartos Biosphere Reserve (Mexico, about 60%), West Coast National Park (South Africa, about 40%) and Celestún Biosphere Reserve (Mexico, about 40%). All parks ranked.
Same genus: Thalasseus
The closest relatives of the Sandwich Tern that you can see in Las Baulas Marine National Park (genus Thalasseus, Crested Terns) are Royal Tern (about 30%) and Elegant Tern (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Sandwich Tern is recorded against all the birds logged in Las Baulas Marine National Park (103 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.
