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  • Scientific Name: Catharus mexicanus
  • Spanish Name: Zorzal cabecinegro
  • Family: Turdidae
  • Known Nicknames: Black-headed Nightingale Thrush
  • Average Length: 15–17 cm / 5.9–6.7 in
  • Average Weight: 26–32 g / 0.92–1.13 oz
  • Envergure : N/A
  • Key Feature: Uniformly dark slate-gray head and breast contrasting with olive-brown upperparts and whitish belly
  • Primary Diet: Primarily Insectivore and Frugivore
  • Range: Southern Mexico south through Central America to western Panama
  • Habitat: Humid montane and lowland evergreen forest understory, often near streams
  • Social Structure: Solitary or in pairs during breeding; loosely associated in mixed-species flocks outside breeding season
  • Nesting/Breeding: Cup-shaped nest placed in a fork of a shrub or small tree, typically low to the ground
  • Statut de conservation : Préoccupation mineure (LC)
  • Évolution démographique : Stable

The Black-headed Nightingale-Thrush (*Catharus mexicanus*) is a secretive jewel of the cloud forests, distinguished by its striking slate-gray body that sharply contrasts with a glossy black hood and a bright, clean white belly. This medium-sized thrush, found from central Mexico to Panama, is more often heard than seen, possessing a hauntingly beautiful, flutelike song that spirals through the mist. Its most unique characteristic is a set of vivid, reddish-orange eye-rings and a similarly colored bill base, which give it an alert, almost painted expression. Unlike many thrushes, it forages low in dense undergrowth, often cocking its tail and flicking its wings nervously, while its presence in high-altitude, moss-laden forests makes it a prized sighting for birders seeking the region's most melodic and elusive species.

Faits amusants

Despite its scientific name *Catharus mexicanus*, this bird is actually found from central Mexico down through Central America, not just in Mexico. It has a quirky habit of tilting its head and flicking its wings rapidly while foraging, a motion that may help startle hidden insects into movement. Its song is a haunting, flutelike series of notes that descends in pitch, often delivered from a hidden perch in dense understory, and it is one of the few thrushes known to mimic the calls of other bird species, though rarely. Uniquely, it builds a bulky cup nest lined with moss and rootlets, sometimes incorporating colorful bits of fungus or flowers, possibly as camouflage or a mate-attracting decoration.

Habitats et répartition

The Black-headed Nightingale-Thrush is found primarily in the highlands of Central America, ranging from southern Mexico through Guatemala, Honduras, El Salvador, and into western Nicaragua. Its distribution is closely tied to humid montane forests, cloud forests, and mature second-growth woodlands at elevations typically between 900 and 3,000 meters. It prefers dense, shady understory with abundant moss, leaf litter, and tangled vegetation, often near streams or ravines. This thrush is generally resident within its range, though it may make minor altitudinal movements in response to seasonal changes.

Comportements & Reproduction

The Black-headed Nightingale-Thrush is primarily solitary outside of the breeding season, maintaining loose territories through song. Mating pairs form seasonally, and courtship involves the male performing a series of soft, complex songs while following the female through the understory, occasionally offering food items as a nuptial gift. The pair builds a bulky, cup-shaped nest of moss and leaves, typically placed in a tree fork or on a horizontal branch. A unique reproductive strategy is the female’s use of a specialized, mud-lined nest cup to cement the structure, which helps it withstand heavy tropical rains. Clutch size is usually two to three pale blue eggs with brown speckles, and incubation is performed solely by the female, lasting about 13–14 days. The male assists with feeding the chicks after hatching, and fledglings leave the nest after approximately 12–15 days, though they remain dependent on the parents for several more weeks.

Alimentation

The Black-headed Nightingale-Thrush (Catharus mexicanus) is primarily a frugivore and insectivore, with its diet shifting seasonally based on availability. It forages on or near the forest floor, often in damp, shaded areas, where it consumes a wide variety of small invertebrates such as beetles, ants, caterpillars, and spiders during the breeding season to meet high protein demands. In the non-breeding season or when insects are scarce, it heavily relies on fruits and berries, particularly favoring small, soft fruits like those from melastomes and other understory shrubs. An interesting fact is that this thrush plays a key role in seed dispersal, as it swallows fruits whole and passes the seeds intact, helping to regenerate its tropical montane forest habitat. Additionally, it has been observed occasionally following army ant swarms to capture insects flushed out by the ants, a behavior more common in antbirds but also used by this thrush to exploit a temporary food bonanza.

Couleurs

The Black-headed Nightingale-Thrush has a slate-gray head, nape, and upper breast contrasting sharply with a rich olive-brown back, wings, and tail. Its underparts are pale grayish-white, with a faint buff wash on the flanks and belly, while the throat is white with subtle dark streaking. Unique features include a pale eye-ring and a blackish bill, with no bold patterns or camouflage adaptations, relying instead on its subdued, uniform coloration to blend into dense understory shadows.