Gelochelidon macrotarsa
In 3 days ~20% in a week ~30%
The Australian tern or Australian gull-billed tern (Gelochelidon macrotarsa) is a tern in the family Laridae, native to Australia. The genus name is from Ancient Greek gelao, "to laugh", and khelidon, "swallow". John Gould described Sterna macrotarsa from a specimen held at King's College, London in 1837. Although first described as a species, throughout most of the 20th and early 21st centuries it was generally considered to be a subspecies of the gull-billed tern, but was re-elevated to species status by the IOC World Bird List in 2019 in its Version 9.2.
This is a fairly large and powerful tern, similar in size and general appearance to a Sandwich tern, but the short thick gull-like bill, broad wings, long legs and robust body are distinctive. The summer adult has pale grey upperparts, white underparts, a black cap, strong black bill and black legs. The call is a characteristic ker-wik. It is 33–42 cm (13–17 in) in length and 76–91 cm (30–36 in) in wingspan. Its weight ranges from 150–292 g (5.3–10.3 oz). It differs from the closely related gull-billed tern in being slightly larger, paler grey above, and with an obviously larger, heavier bill.
In... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cape Range | 🇦🇺 Australia | |
| 2 | Ningaloo Marine Park | 🇦🇺 Australia | |
| 3 | Noosa National Park | 🇦🇺 Australia | |
| 4 | Kakadu National Park | 🇦🇺 Australia | |
| 5 | Daintree National Park | 🇦🇺 Australia |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Brisbane | 🇦🇺 Australia |
With luck
About 10% of wildlife watchers report an Australian Tern sighting in Kakadu National Park on a given day, based on 78 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 116th most-seen of the 186 birds we can rate there. Over three days the chance rises to about 20%, and over a week to about 30%, if each day is a fresh chance.
July and September
In those months about 10% of wildlife watchers report an Australian Tern in Kakadu National Park on a given day, against under 5% in March–June, August and October–January, the lowest months. Those are among Kakadu National Park's driest months, with about 15 mm of rain a month against 350 mm in January. February has too few records to rate.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Australian Tern sightings with a recorded time, and nearly all of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 5 parks where we can rate Australian Tern sightings, Kakadu National Park ranks 4th at about 10%, level with the leaders once rounded. The best odds are in Cape Range (Australia, about 10%), Ningaloo Marine Park (Australia, about 10%) and Noosa National Park (Australia, about 10%).
GBIF citizen-science records
It is estimated from how often the Australian Tern is recorded against all the birds logged in Kakadu National Park (78 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.
