Here at our mountain retreat, nestled amidst the emerald embrace of Costa Rica’s central highlands, we focus on the symphony of birdsong that fills the crisp morning air. But Costa Rica’s avian diversity extends far beyond the lush rainforests and towering volcanoes. Today, we set our sights skyward, to a majestic visitor gracing our Pacific and Caribbean coasts – the Caspian Tern.

A Global Citizen with a Local Flair

The Caspian Tern, with its scientific name Hydroprogne caspia, is aptly named. Early ornithologists associated it with the Caspian Sea, reflecting its vast global range. This magnificent bird holds the title of the largest tern in the world, boasting a wingspan that rivals a Black-backed Gull. Despite its extensive distribution, the Caspian Tern is a solitary nester, and Costa Rica serves as a wintering ground for these impressive migrants.

Spotting a Master of the Skies

So, how can you identify a Caspian Tern gracing the Costa Rican coastline? Keep an eye out for these key features:

• Size & Shape: The Caspian Tern is a true giant among terns, measuring 47-54 cm in length with a wingspan reaching a staggering 1 meter. Its body is sleek and streamlined, with a short, slightly forked tail compared to other terns.
• Coloration: Adults in breeding plumage are a sight to behold. The upperparts are a shimmering silver-grey, contrasting beautifully with the snow-white underparts. The wings display dark tips, adding a touch of drama.
• The Beak: Undoubtedly the showstopper is the Caspian Tern’s formidable beak. This bright red “fish-knife” is a powerful tool for hunting prey, and its color intensifies during the breeding season.
• Headwear: During breeding season, adults sport a sleek black cap that extends below the eye. This cap gives way to a speckled white crown during the non-breeding months.

A Life on the Wing

The Caspian Tern is a master of aerial acrobatics. With powerful wings and a streamlined body, it soars effortlessly over coastal waters, freshwater lakes, and even rivers. These opportunistic predators are adept at plunge-diving, plummeting from great heights to snatch fish from the water’s surface with their sharp beaks. Their diet also includes crustaceans and insects.

A Forceful Defender

Caspian Terns are fiercely protective of their nesting colonies, which are often located on small islands or sandbars. They will aggressively chase away any perceived threats, including other birds and even humans who venture too close. Here at the retreat, while we may not see the nesting colonies ourselves, their presence along the coasts adds another layer of wonder to Costa Rica’s ecological tapestry.

A Glimpse of Global Connections

The Caspian Tern’s presence in Costa Rica is a reminder of the interconnectedness of our planet. These feathered nomads travel vast distances, gracing our shores with their regal presence. So, the next time you find yourself on a Costa Rican beach, keep your eyes peeled for the Caspian Tern – a powerful symbol of the avian wonders that Costa Rica has to offer.

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

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