Birda Logo
A photo of a Least Tern (Sternula antillarum)
Least Tern

Least Tern

Sternula antillarum

The Least Tern (Sternula antillarum), a diminutive seabird, graces the skies of North America and parts of northern South America. With a length of 22–24 cm and a wingspan of 50 cm, it is the smallest of its kind in its range. The upper parts of this bird are a pale gray, while the underparts are a pristine white. During the breeding season, it sports a striking black cap and a line through the eye extending to the bill's base, complemented by a small white patch on the forehead. In the winter, the black cap recedes, giving way to a more prominent white forehead. The bill, a vibrant yellow with a black tip in summer, darkens in the colder months, as do the yellowish legs. In flight, the Least Tern is easily recognized by its rapid wingbeats and its characteristic hunchbacked silhouette, with the bill angled slightly downward.

Identification Tips

When identifying the Least Tern, look for the black markings on the outermost primaries of its pale gray wings. The combination of its small size, pale gray and white plumage, and distinctive flight pattern are key to distinguishing it from other tern species.


The Least Tern favors a variety of coastal habitats, including sandy beaches, estuaries, and river sandbars. It is also known to adapt to human-altered environments, such as gravel rooftops, for nesting.


This migratory bird spends its winters in Central America, the Caribbean, and northern South America. It has been recorded as a vagrant in Europe, with sightings in Great Britain and Ireland.


The Least Tern is a migratory species, with many individuals spending their entire first year in their wintering areas. It is known for its agile flight over water as it searches for fish.

Song & Calls

The call of the Least Tern is a high-pitched, squeaky sound, distinct from the calls of similar species such as the Little Tern.


Breeding takes place from late April, with colonies forming along marine shores, estuarine shores, or river sandbars. Courtship involves aerial displays or feeding, and nesting begins by mid-May. The species is known for its low nest density and clutch sizes ranging from one to four eggs.

Similar Species

The Least Tern can be differentiated from the Little Tern by its gray rump and tail, as opposed to the Little Tern's white, and by its unique call. It is paler than the Yellow-billed Tern and has a black-tipped bill, unlike the all-yellow bill of the latter. The Peruvian Tern is also similar but has a longer black tip on the bill and a pale gray underside.

Diet and Feeding

The diet of the Least Tern primarily consists of small fish such as silversides, smelt, and anchovies, which it catches by hovering and plunging into shallow waters. It may also consume insects during certain environmental conditions.

Conservation status

The Least Tern has three subspecies with varying conservation statuses. The S. a. antillarum is not federally threatened but is considered threatened in several states. The interior subspecies, S. a. athalassos, was previously listed as endangered due to habitat loss but was delisted in 2021. The California subspecies, S. a. browni, remains endangered despite a rebound in population numbers due to conservation efforts. Predation and human disturbance continue to pose threats to the species.

Least Tern Sounds

Recorded by: © 
App logo
Birda is a birdwatching app and community aimed at curious people who want to deepen their connection with nature.

Least Tern Fun Facts

Did you know?
The Least Tern is the smallest species of Tern in the world.

Least Terns on Birda


More Gulls, Terns, Skimmers

Birda Logo

Your birdwatching journey like never before

Connect with nature in minutes
Take a walk, look out of the window and log the birds that you see. Feel good about those little connections to nature.
Discover the joy of birding
Find new birding spots, see more birds, share and celebrate with a like-minded community of nature lovers.
Play your part in saving nature
Logging your birding sightings and sessions turns into positive action for our planet. Every sighting counts.

Birda Blog

What Our Birders Say
Really great app
It’s easy to use and it’s fun to log the birds you notice on a walk or just in your garden. There’s a option to record the birds you see in a session which is really nice. Good excuse to stop for a while and just watch birds. I am also enjoying the information part where you can find out fact about birds from all over the world.
Very Wholesome App
Joined this app with a new interest in watching birds to help me find out what I was spotting. The community is very active in helping identify birds which is great and everyone is very kind so it’s just a nice wholesome community. I would definitely recommend this for any bird spotter 😄
Carl B
Helped me to identify more birds
Love this app and has helped me to identify more birds. The challenges and badges are great for keeping the motivation going to get out and keep birding.
Jane N
A great app
Enjoying it immensely and finding it useful too. Recording the different birds and counting them is showing me how the present climate is affecting them all. I've trebled the numbers by planting native hedging. A great app.
Robred 2
Fun way to add to your birdwatching experience
I enjoy watching birds in my backyard, but this app helped me really pay attention while on vacation this summer. It was fun to add new birds to my bird watching app.
Dan R
Great app for bird fanatics
Great app for bird fanatics - very user friendly and a perfect place to share sightings.
Just what birding needs
We need more fun in birding, for years it has had a reputation for being up tight and stuffy and only perused by retirees and anoraks. Birda helps change that perception and firmly brings birding into the 21st century! Fun, interactive while still contributing to science and conservation. If you aren’t on it, why not??
Great app for beginner twitchers
I’ve had a passion of photographing birds for a long time now but have only just gotten into proper birdwatching, and this app is brilliant for those just getting started. There is a great sense of community among users and the app is very easy to use and professional. Awesome app altogether
Mike T
Sense of Community
A great app, which is continually being improved. What really comes through is the passion of those behind the app. The sense of community is brilliant, so much help and support provided to new and/or in experienced birders.
Ideal Birdwatch Companion
Simply adds to the enjoyment of my birdwatching and helps me record what I’ve seen.
As featured in
Connect with nature,
Find your flock
Download Birda - QR Code
© 2024 All rights reserved