Blue-and-black Tanager

En bref

  • Scientific Name: Tangara vassorii
  • Spanish Name: Tangara azulinegro
  • Famille : Thraupidae
  • Known Nicknames: Blue-and-black Tanager, Vassor's Tanager
  • Longueur moyenne : 13–14 cm / 5,1–5,5 pouces
  • Average Weight: 14–20 g / 0.49–0.71 oz
  • Envergure : N/A
  • Key Feature: Deep blue plumage with black face, wings, and tail
  • Primary Diet: Primarily Frugivore, also insectivorous
  • Range: Andes of Colombia, Ecuador, Peru, and Bolivia
  • Habitat: Montane cloud forest, forest edges, and shrubby clearings
  • Social Structure: Highly Social, often in mixed-species flocks
  • Nesting/Breeding: Cup-shaped nest in tree or shrub
  • Statut de conservation : Préoccupation mineure (LC)
  • Évolution démographique : Stable

The Blue-and-black Tanager (*Tangara vassorii*) is a stunning, high-altitude gem of the Andean cloud forests, distinguished by its striking, almost metallic plumage. Its unique coloration features a deep, velvety black head and body, dramatically contrasted by brilliant cobalt-blue wings, tail, and a vivid blue crescent on the chest. A special feature of this species is its subtle iridescence; under direct sunlight, the blue patches shimmer with an electric, turquoise sheen, while the black feathers may reveal hidden greenish highlights. This tanager is also notable for its specialized foraging behavior, often seen gleaning insects and fruit while hanging upside down from mossy branches, a trait shared by few other tanagers.

Faits amusants

Despite its name, the Blue-and-black Tanager is not strictly blue and black; its vivid turquoise feathers can appear almost electric under direct sunlight, a trick of structural coloration rather than pigment. It has a quirky habit of hanging upside down like a titmouse to pry loose insects and fruit from the undersides of leaves, often joining mixed-species flocks where it acts as a hyperactive scout. One unique adaptation is its ability to digest the waxy coating of certain berries that other birds avoid, giving it a specialized niche in high-altitude cloud forests.

Habitats et répartition

The Blue-and-black Tanager is found along the eastern slope of the Andes from southern Colombia through Ecuador and Peru into central Bolivia. It inhabits humid montane forest, cloud forest, and adjacent edges, typically at elevations between 2,000 and 3,300 meters. It is often associated with mossy, epiphyte-laden trees and is commonly seen in the canopy or along forest borders, where it forages in mixed-species flocks.

Comportements & Reproduction

Blue-and-black Tanagers are typically observed in small, stable social groups of three to six individuals, often family units, that forage together through the canopy. Their social structure is based on a monogamous pair bond, which is maintained across multiple breeding seasons. Courtship involves the male performing a series of soft, high-pitched calls while fluttering his wings and hopping in an exaggerated, sideways display near the female. Nest building is a shared task, with both sexes constructing a cup-shaped nest of moss and plant fibers, usually placed in a dense fork of a tree or shrub. The female lays two pale, speckled eggs, and incubation lasts about 13–14 days, during which the male regularly brings food to the nest. Both parents feed the chicks, which fledge after roughly 15–18 days, but the young often remain with their parents for several weeks after fledging, contributing to the group’s cooperative foraging dynamic. No unique reproductive strategies, such as cooperative breeding or brood parasitism, have been documented for this species.

Alimentation

The Blue-and-black Tanager is primarily frugivorous, with a diet heavily centered on a variety of small, soft fruits and berries, which it plucks directly from branches or while hovering. It also actively forages for arthropods, including small insects, spiders, and caterpillars, which provide essential protein, especially during the breeding season. An interesting aspect of its feeding behavior is that it often joins mixed-species foraging flocks, moving through the canopy and understory with other tanagers and birds to efficiently locate fruit sources and flush out hidden insects. Additionally, it has been observed taking nectar from flowers, supplementing its diet with this sugary resource when available.

Couleurs

The Blue-and-black Tanager (Tangara vassorii) displays a striking contrast of deep, glossy black on the head, wings, tail, and underparts, set against a vivid cerulean blue on the mantle, back, and rump. It has no unique camouflaging patterns, but its bright coloration serves as a visual signal in its Andean cloud forest habitat, with subtle iridescence on the blue feathers that can shift in hue depending on light.