Here at our Costa Rican mountain retreat, we revel in the symphony of birdsong that fills the crisp mountain air. But Costa Rica’s avian diversity extends far beyond our lush highlands. Today, we set our sights on the coast, where a diminutive wonder takes flight – the Least Tern.

True to its name, the Least Tern is the smallest member of the tern and gull family. Imagine a bird barely bigger than a robin, with a delicate frame and a wingspan that wouldn’t even cover your outstretched arms. These pint-sized marvels grace Costa Rica’s Pacific and Caribbean coasts from late August to late October, and then again briefly in April [1].

While you won’t find Least Terns flitting through our mountain retreat, birding enthusiasts venturing to Costa Rica’s beaches have a good chance of encountering these fascinating creatures. Keep your eyes peeled for their pale grey upperparts and bright white underbellies, creating a sharp contrast as they gracefully swoop and dive.

A master of aerial acrobatics, the Least Tern hunts small fish by plunging headfirst from impressive heights. Their sharp eyesight allows them to spot prey from afar, and their agile bodies ensure they can maneuver mid-air to snatch their prize.

Least Terns are social birds, often nesting in colonies on open, sandy beaches or sandbars along rivers and lakes. They create simple nests by scraping shallow depressions in the sand, sometimes lining them with pebbles or debris [2].

These tiny birds face challenges. Their reliance on open sandy areas makes them vulnerable to habitat loss due to development. Predators like foxes and raccoons also pose a threat to their eggs and chicks. Conservation efforts are underway to protect nesting sites and ensure the continued survival of the Least Tern.

So, if you find yourself basking on a Costa Rican beach, keep an eye out for these feathered flyweights. The Least Tern, though tiny in stature, is a captivating reminder of the beauty and resilience of the natural world.

Spotting Tips:

• Look for Least Terns on open, sandy beaches, riverbanks, and lakeshores.
• Pay attention to their distinctive grey and white plumage and black cap.
• Watch for their characteristic diving behavior as they hunt for fish.

Listen for: High-pitched calls and whistles.

By being mindful visitors to Costa Rica’s precious ecosystems, we can all help ensure that future generations can witness the wonder of the Least Tern.

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

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