Crested Hornero

Characterized by a small and compact silhouette, this passerine measures between 5.5 to 5.9 inches (14 to 15 centimeters) in length and weighs approximately 26 to 31 grams, making it the smallest member of its genus. Its most distinctive morphological feature is a prominent, erectile crest on the crown, which it raises when excited or vocalizing. The dorsal plumage is predominantly sandy-brown with a subtle rufescent wash, transitioning to a pale creamy-buff on the breast and belly, while the throat is a contrasting whitish tone. The bill is medium-sized, slender, and slightly decurved, with a brownish-gray coloration that matches its terrestrial foraging habits.

Geographical distribution: Restricted to the South American continent, specifically within the Chaco biome. Its range encompasses western and central Paraguay, extreme southeastern Bolivia (primarily in the departments of Tarija and Santa Cruz), and extensive areas of northern and central Argentina, extending southward to the provinces of San Luis, Córdoba, and northern La Pampa.

Habitat: Prefers semi-arid and arid landscapes, showing a strong affinity for xerophytic woodlands, thorn forests, and dry scrublands. It is frequently encountered in areas with sparse ground cover and sandy soils, as well as degraded savanna-like pastures, rural gardens, and roadside edges where native trees like Prosopis and Acacia are present.

Feeding: Highly insectivorous, its diet relies heavily on a wide variety of ground-dwelling invertebrates. Key prey items include ants, beetles, spiders, grasshoppers, and various insect larvae. It searches for food by walking deliberately on the ground, using its bill to toss aside dry leaves, probe soil crevices, and dig into loose dirt to extract hidden prey.

Behavior: Primarily terrestrial, this species spends most of its active hours walking or running on the ground with a characteristic head-bobbing gait. It is typically found singly or in stable, monogamous pairs. Partners maintain territory boundaries through loud, ringing vocal duets consisting of rapid, metallic notes, often performed while perched on low branches with wings shivering and crests fully raised.

Nesting: Builds a dome-shaped chamber made of mud, commonly known as an oven-nest, which is structurally similar to but significantly smaller than that of its larger relatives. The construction material consists of a mixture of wet clay, manure, and dry straw, which hardens into a durable structure. These nests are typically situated at low heights, usually 3 to 10 feet (1 to 3 meters) above the ground, placed on horizontal branches of thorny trees or fence posts. The clutch consists of 2 to 3 pristine white eggs, incubated by both adults for about 15 to 18 days, with both parents sharing the duties of feeding and protecting the chicks.

Conservation status: Currently evaluated as Least Concern (LC) on the IUCN Red List. Although the Chaco region faces severe pressure from deforestation and agricultural expansion, this species shows high ecological resilience, successfully adapting to edge habitats, cleared areas, and agricultural landscapes, ensuring its overall population remains stable.