Here at our Costa Rican mountain retreat, we encourage you to not only appreciate the majesty of the peaks but also delve into the rich tapestry of life that thrives in the diverse ecosystems of our country. Today, we turn our focus to a little-seen resident of the tropical lowlands, the aptly named Masked Duck.

A Master of Disguise

The Masked Duck (Nomonyx dominicus) is a true master of camouflage. This tiny diving duck, barely larger than a teal, prefers the quiet seclusion of freshwater marshes, ponds, and even roadside ditches. While uncommon visitors to our mountain retreat, if you ever find yourself exploring the vibrant lowlands of Costa Rica, keep an eye out for these elusive birds.

A Glimpse into Hidden Lives

Unlike many ducks, the Masked Duck is primarily nocturnal. During the day, they vanish into the dense marsh vegetation, their subdued brown bodies offering exceptional concealment. Their stocky build and stiff tails further aid in their quest for invisibility. Your best chance of spotting one is in the early morning or late afternoon, when they might emerge for feeding forays.

Distinctive Beauty Revealed

While fleeting glimpses might be the norm, a lucky encounter with a Masked Duck in good light is a sight to behold. The males, in breeding plumage, are a revelation. Their namesake black mask sharply contrasts with a bright blue bill, adding a touch of charisma to their dark, rusty-brown bodies.

Females, though less flashy, are no less beautiful. Their brown feathers are adorned with a delicate buff face, accentuated by two bold, dark stripes.

A Symphony of the Night

The Masked Duck’s secretive nature extends to their vocalizations. Unlike their boisterous cousins, these ducks are remarkably quiet. Their calls are described as soft whistles or grunts, rarely heard by human ears.

A Vital Part of the Ecosystem

Despite their elusiveness, Masked Ducks play a crucial role in the health of wetland ecosystems. They are omnivores, their diet consisting mainly of aquatic plants, seeds, and small invertebrates. By keeping these populations in check, they help maintain the delicate balance of the wetlands.

Where to Look for the Masked Duck

While not found in the highlands where our retreat resides, Masked Ducks have a wide range across the Costa Rican lowlands. From the Caribbean to the Pacific coast, they frequent marshes, freshwater lagoons, and even man-made ponds. Some potential areas to look for them include:

• Palo Verde National Park
• Cañas River National Wildlife Refuge
• Terraba- Sierpe National Wetland
• Tempisque River Basin

A Challenge for Birdwatchers

Seeing a Masked Duck is a rewarding experience for any birdwatcher. Their secretive nature and preference for dense cover make them a delightful challenge to spot. But with patience, a keen eye, and a visit to Costa Rica’s vibrant lowlands, you might just be rewarded with a glimpse of this shy diver.

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

This post is also available in: Français (French) Español (Spanish)