Here at the Costa Rican Retreat, nestled amidst the emerald embrace of the mountains, we revel in the symphony of birdsong that fills the air. But our feathered friends extend far beyond the vibrant toucans and melodic wrens that grace our rainforests. Today, we set our sights on the coast, to meet a nocturnal anomaly – the Swallow-tailed Gull.
Forget the squawking, bread-stealing gulls you might picture at the beach. The Swallow-tailed Gull is a creature of elegance and mystery. Unlike its close relatives, this gull thrives under the cloak of darkness. With the largest eyes of any gull species, it possesses exceptional night vision, allowing it to hunt squid and fish while the rest of the world sleeps.
This ghostly beauty isn’t a common sight in Costa Rica. It finds its home primarily in the Galapagos Islands, venturing as far south as Peru during its non-breeding season. However, a keen birder might be lucky enough to spot them on the Pacific Coast of Costa Rica, particularly offshore waters near the Gulf of Nicoya.
A Master of the Night
The Swallow-tailed Gull’s nocturnal habits are a result of several adaptations. Their large eyes, equipped with a special reflective layer, capture every sliver of moonlight. Some theories suggest they might even use echolocation, similar to bats, to navigate the darkness with clicking sounds. This unique skill allows them to avoid competition with frigatebirds, notorious kleptoparasites that steal food from other birds during the day.
A Looker in the Moonlight
While shrouded in darkness during their hunt, Swallow-tailed Gulls are a sight to behold in daylight. Their plumage is a study in contrasts – pearly gray bodies with contrasting black heads and a stunning, three-toned wing pattern of black, white, and gray. Adults sport a vibrant red eyering and pinkish legs, adding a touch of panache. Juveniles are no less striking, with a dark, scaly upper body that gradually transitions to a white head as they mature.
A Life on the Edge
Swallow-tailed Gulls are pelagic birds, meaning they spend most of their lives soaring over the open ocean, rarely venturing near land. They are solitary creatures, coming together only to breed on the cliffs of the Galapagos Islands. Here, they form loose colonies, laying a single egg each season. Both parents take turns incubating the egg and fiercely defending their young.
A Glimpse of the Extraordinary
Spotting a Swallow-tailed Gull on the Pacific Coast of Costa Rica is a rare privilege. But even the possibility of encountering this enigmatic creature adds another layer of wonder to the rich tapestry of Costa Rican birdlife. So, the next time you find yourself on the shores of our beautiful country, keep your eyes peeled for a flash of white and black against the twilight sky. You might just catch a glimpse of the night owl of the gull world.
For more information, please view our comprehensive guide about the birds of Costa Rica
