Gelochelidon nilotica
Silhouette: Sheatherius · PhyloPic
In 3 days ~90% in a week >90%
The gull-billed tern (Gelochelidon nilotica) is a tern in the family Laridae. It is widely distributed and breeds in scattered localities in Europe, Asia, northwest Africa, and the Americas. The Australian gull-billed tern was previously considered a subspecies.
The gull-billed tern was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with terns in the genus Sterna and coined the binomial name Sterna nilotica. Gmelin based his description on the "Egyptian tern" that had been described in 1785 by the English ornithologist John Latham in his book A General Synopsis of Birds. Latham had in turn based his own account on that by the Swedish naturalist Fredrik Hasselquist that was published in 1757. The gull-billed tern was moved to the resurrected genus Gelochelidon based on a molecular phylogenetic study published in 2005. The genus had been introduced in 1830 by the German zoologist Christian Ludwig Brehm. The genus name combines the Ancient Greek gelaō meaning "to laugh" with khelidōn meaning "swallow". The specific epithet nilotica is from Latin niloticus meaning... Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Zanzibar City | 🇹🇿 Tanzania | |
| 2 | Karachi | 🇵🇰 Pakistan | |
| 3 | Kuwait City | 🇰🇼 Kuwait | |
| 4 | Manama | 🇧🇭 Bahrain | |
| 5 | São Luís | 🇧🇷 Brazil | |
| 6 | Dakar | 🇸🇳 Senegal | |
| 7 | Dar es-Salaam | 🇹🇿 Tanzania | |
| 8 | Barranquilla | 🇨🇴 Colombia | |
| 9 | Luxor | 🇪🇬 Egypt | |
| 10 | Mumbai | 🇮🇳 India |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Zoobotánico Jerez | 🇪🇸 Spain |
Likely
About 60% of wildlife watchers report a Gull-billed Tern sighting in Zanzibar City on a given day, based on 155 verified sightings from GBIF citizen-science data. It is the 13th most-seen of the 86 birds we can rate there. Over three days the chance rises to about 90%, and over a week to over 90%, if each day is a fresh chance.
March and December
In those months about 80% of wildlife watchers report a Gull-billed Tern in Zanzibar City on a given day, against about 30% in May to July, the lowest months.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Gull-billed 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.
Yes
Of the 52 cities where we can rate Gull-billed Tern sightings, Zanzibar City has the highest daily chance: about 60%. Next come Karachi (Pakistan, about 30%) and Kuwait City (Kuwait, about 30%).
Same family: Laridae
The closest relatives of the Gull-billed Tern that you can see in Zanzibar City (family Laridae, Gulls, Terns, and Skimmers) are Sooty Gull (about 40%), Lesser Crested Tern (about 40%) and Crested Tern (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Gull-billed Tern is recorded against all the birds logged in Zanzibar City (155 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.
