Here at our mountain retreat, nestled amidst the emerald embrace of Costa Rica’s highlands, we celebrate the incredible diversity of birds that grace our skies. While our location might not be the first that comes to mind for spotting terns, a special visitor sometimes makes a surprise appearance – the Yellow-billed Tern (Sternula superciliaris).

Primarily a resident of South America, the Yellow-billed Tern is a tiny seabird with a bright yellow beak, the source of its namesake. Though uncommon in Costa Rica, with only a handful of documented sightings, this little wonder can occasionally be spotted by keen observers.

A Flash of Gray and White

The Yellow-billed Tern boasts a plumage that changes with the seasons. During breeding season (August to December in South America), it dons a striking black crown that contrasts beautifully with its pale gray back and snow-white underparts. A small, white patch adorns its forehead, adding a touch of charm.

Outside of breeding season, the black crown gives way to a clean white head, with a darker mask around the eyes. This mask helps distinguish it from the Least Tern, a similar species sometimes seen in Costa Rica. The Yellow-billed Tern also has a slightly thicker, lacks the black tip on its bill that the Least Tern possesses.

A Life by the Water’s Edge

While the mountains are our domain, the Yellow-billed Tern prefers life by freshwater sources. Look for it gliding gracefully over large rivers, lakes, and swamps. It might even venture to the coast during the non-breeding season, frequenting coastal lagoons, river mouths, and even rice fields.

A master of aerial acrobatics, the Yellow-billed Tern dives headfirst into the water to catch small fish, its sharp beak perfectly adapted for snatching its prey. It often nests in colonies alongside other tern species, creating shallow scrapes in the sand as its home.

A Glimpse of the Unexpected

Spotting a Yellow-billed Tern in Costa Rica is a truly special event. If you’re lucky enough to see this rare visitor during your stay at our retreat, keep your binoculars handy! Observe its graceful flight, the flash of yellow on its beak, and the unique markings on its head depending on the season.

While the Yellow-billed Tern might not be a permanent resident of our mountain haven, its occasional presence reminds us of the interconnectedness of Costa Rica’s ecosystems. Even in the heart of the highlands, there’s always the chance of encountering a surprising avian wonder.

For more information, please view our comprehensive guide about the birds of Costa Rica

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