Thalasseus maximus
Silhouette: Andy Wilson · PhyloPic
In 3 days ~20% in a week ~40%
The royal tern (Thalasseus maximus) is a tern in the family Laridae. The species is endemic to the Americas, though vagrants have been identified in Europe. The royal tern was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1781 in his Histoire Naturelle des Oiseaux from a specimen collected in Cayenne, French Guiana. The bird was also illustrated in a hand-colored plate engraved by François-Nicolas Martinet in the Planches Enluminées D'Histoire Naturelle which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text. Neither the plate caption nor Buffon's description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name Sterna maxima in his catalogue of the Planches Enluminées. The royal tern is now placed in the genus Thalasseus that was erected by the German zoologist Friedrich Boie in 1822.
The generic name is derived from the Ancient Greek θάλασσα (thálassa) meaning "sea". The specific epithet maximus is Latin for "greatest". The royal tern belongs to the class Aves and the order Charadriiformes. Charadriiformes includes seabirds and shorebirds of small to medium... Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Havana | 🇨🇺 Cuba | |
| 2 | San Diego | 🇺🇸 United States | |
| 3 | Montevideo | 🇺🇾 Uruguay | |
| 4 | Miami | 🇺🇸 United States | |
| 5 | Panama City | 🇵🇦 Panama | |
| 6 | Tijuana | 🇲🇽 México | |
| 7 | Santo Domingo | 🇩🇴 Dominican Republic | |
| 8 | Los Angeles | 🇺🇸 United States | |
| 9 | Vitória | 🇧🇷 Brazil | |
| 10 | Barranquilla | 🇨🇴 Colombia |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Downtown Aquarium, Denver | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Royal Tern sighting in Palo Verde National Park on a given day, based on 127 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 104th most-seen of the 274 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.
February
In that month about 20% of wildlife watchers report a Royal Tern in Palo Verde National Park on a given day, against under 5% in April, June–September and November, the lowest months. That is one of Palo Verde National Park's driest months, with almost no rain against 480 mm in October.
Between 7 and 10 am
Across all the parks we cover, that three-hour window holds the most Royal 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.
30th of 42
Of the 42 parks where we can rate Royal Tern sightings, Palo Verde National Park ranks 30th at about 10%. The best odds are in Padre Island National Seashore (United States, about 80%), Ría Lagartos Biosphere Reserve (Mexico, about 80%) and Jaragua National Park (Dominican Republic, about 50%). All parks ranked.
GBIF citizen-science records
It is estimated from how often the Royal Tern is recorded against all the birds logged in Palo Verde National Park (127 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.
