Ash-colored Cuckoo

Displays a slender and compact body silhouette, characteristic of the smaller representatives of the family Cuculidae, with an overall length ranging from 8.2 to 9.1 inches and a body mass of approximately 35 to 42 grams. Its dorsal plumage exhibits a uniform ash-gray coloration, which covers the crown, mantle, and wing coverts. The underparts are distinctly paler, transitioning from a light gray on the throat and breast to a whitish or buffy hue on the belly and undertail coverts. Adults feature a striking, intense red iris bordered by an inconspicuous, narrow bare orbital ring that ranges from grayish to pale yellow. The bill is relatively short, slightly decurved, and colored dark gray to black. Its long, graduated tail is dark gray, with outer tail feathers tipped in narrow but distinct white bands, which are most visible when the tail is flared during courtship or territorial displays.

Geographical distribution: Occurs widely across South America, functioning as a highly migratory austral species. During the southern spring and summer breeding season, it is found in central and northern Argentina, throughout Paraguay, Uruguay, and southern and southeastern Brazil. With the onset of the austral autumn, populations undertake a northward migration to winter in the Amazon Basin, extending into Bolivia, Peru, Ecuador, Colombia, and Venezuela, where they occupy lowland regions during the non-breeding season.

Habitat: Inhabits a diverse range of wooded and shrubby ecosystems, showing a strong preference for semi-open areas rather than continuous, dense forests. It is frequently observed in Chaco woodlands, gallery forests, riparian thickets, wooded savannas, second-growth forests, and forest edges. Additionally, it adapts well to human-modified landscapes, including agricultural fields with scattered trees, suburban parks, orchards, and gardens, where it utilizes the mid-story and understory vegetation for foraging and shelter.

Feeding: Feeds primarily on insects, displaying a specialized ability to consume hairy and stinging caterpillars that are unpalatable to most other bird species. It utilizes its curved bill to scrape or beat toxic caterpillar hairs against branches before swallowing them. In addition to lepidopteran larvae, its diet regularly includes beetles, grasshoppers, cicadas, spiders, and other forest invertebrates. It occasionally supplements its diet with small wild berries and soft plant buds, especially when insect prey becomes scarce during seasonal transitions.

Behavior: Leads a quiet, solitary, and rather secretive life, often remaining unnoticed due to its cryptic coloration and habit of staying motionless for long periods within dense foliage. Movements are characterized by slow, deliberate hops from branch to branch rather than active flying. Its vocalization is a distinctive, rapid series of dry, rattling notes resembling an insect-like rasp or mechanical clicking sound. During migration, flights are performed mostly at night to minimize the risk of predation by diurnal raptors.

Nesting: Unlike many Old World cuckoos that are obligate brood parasites, this species builds its own nest and rears its own offspring. The nest is a shallow, loosely constructed platform of dry twigs, lined internally with green and dry leaves to help regulate temperature and humidity. It is typically positioned at low to medium heights, between 3 and 13 feet above the ground, well-hidden within the fork of a dense shrub or thorny tree. The clutch consists of 2 to 3 chalky-white eggs with a faint greenish tint. Both parents participate actively in incubating the eggs and feeding the altricial chicks with regurgitated insects.

Conservation status: Categorized as Least Concern (LC) on the IUCN Red List of Threatened Species. Although local populations face challenges from habitat loss, deforestation, and agricultural expansion within its breeding grounds in the Southern Cone, its exceptionally large distribution range and adaptability to fragmented habitats and edge zones suggest that its global population remains stable without immediate threats of extinction.