Chiloe Wigeon

The Chiloé wigeon, or Mareca sibilatrix, presents a striking figure with its iridescent green-blue cap and contrasting white cheeks and forehead. This medium-sized duck boasts a wingspan stretching from 75 to 86 centimeters and a body length ranging between 46 to 56 centimeters. Weighing in at approximately 800 grams, it carries a bluish gray bill capped with black, dark brown eyes, and a distinctive white auricular patch. The neck and rear of the head are cloaked in black, while the breast is adorned with black and white bars. The wings display a muted gray and white plumage, with males flaunting rust-colored flanks and females, a more subdued light brown. Their legs and feet are a matching shade of gray.

Identification Tips

When attempting to identify the Chiloé wigeon, look for the subtle sexual dimorphism that exists within the species. Males are generally larger and heavier than females, with more vivid plumage and a pronounced iridescent sheen on their caps. Juveniles share a resemblance with adults but lack the rust coloring on their flanks.

Habitat

The Chiloé wigeon is a denizen of freshwater lakes, marshes, shallow lagoons, and slow-flowing rivers in the southern realms of South America.

Distribution

Native to South America's southern territories, including the Chiloé Archipelago, this species breeds primarily in Argentina, Uruguay, and Chile. It migrates to southeastern Brazil during the winter months and has been introduced to Europe since 1870.

Behaviour

This omnivorous bird displays a variety of behaviors tailored to its habitat. It feeds predominantly on aquatic plants, grass, and occasionally coastal algae. The Chiloé wigeon is monogamous, with pairs establishing small breeding territories. The male plays an active role in raising the ducklings but departs after they molt.

Song & Calls

The species name, sibilatrix, translates to 'whistler', hinting at the bird's vocalizations.

Breeding

Breeding occurs in the austral spring, from September to December. Nests are constructed in grasses and under bushes, where the female lays eight to ten white or cream-colored eggs. After a gestation period of around 24–25 days, the ducklings hatch.

Diet and Feeding

The Chiloé wigeon is an omnivore, with a diet consisting mainly of aquatic plants, grass, and sometimes coastal algae.

Conservation status

The Chiloé wigeon is classified as Least Concern by the IUCN, thanks to its wide distribution and stable population numbers.