Mountain Grackle Macroagelaius subalaris Scientific name definitions

Also known as the Colombian Mountain Grackle, this species is currently treated as Endangered by BirdLife International on accounts of its tiny range and heavily fragmented habitat. The Mountain Grackle is a slim-bodied and exceptionally long-tailed icterid, entirely black with a purple-blue iridescence, except for the dark chestnut axillaries and epaulets, which are only likely to be obvious in very good views. It occurs mainly along the western slope of the East Andes, where the species inhabits subtropical and temperate forests (especially of oak) at elevations of 2400–2900 m, and the Mountain Grackle is suspected to be most common in the Yariguíes mountains. This species is usually found in small groups, and it is suspected to be a cooperative breeder.

Male 29–30 cm, female 27–28 cm. Slender and long-tailed icterid. Plumage is almost entirely black with blue gloss; axillaries and most of underwing-coverts dark chestnut (almost invisible in field); iris dark brown; bill and legs black. Differs from similar M. imthurni mainly in having chestnut in wing, no yellow pectoral tufts, slightly thicker bill , slimmer body. Sexes similar. Juvenile is less glossy and more dusky brown, particularly in flight-feathers, than adult, and with reduced chestnut in wing.

E Andes of Colombia from Norte de Santander and Santander (including Serranía de los Yariguíes) S on W slope to Boyacá (formerly also Cundinamarca).

Humid upper montane forest rich in epiphytes, particularly oak forest (Quercus humboldtii), up to páramo; 1900–3100 m.

Apparently resident.

Feeds on insects and other arthropods, particularly weevils (Curculio­nidae), Orthoptera, bugs (Hemiptera), hymenopterans and spiders (Araneae); takes berries of Oreopanax floribundum (Araliaceae) and Hedyosmum bonplandianum (Chlorantha­ceae). Forages mostly at height of 15–30 m, searching for food items among leaves , inflorescences and epiphytes. Drinks from water stored in tank bromeliads. Found in groups of up to 40 individuals; sometimes in mixed-species foraging flocks with Acorn Woodpecker (Melanerpes formicivorus), Green Jay (Cyano­co­rax yncas), Great Thrush (Turdus fuscater), Hooded Mountain-tanager (Buthraupis montana), Icterus nigrogularis and Cacicus leucoramphus.

Song variable, sometimes starting with low clicks and buzzing notes, followed by series of different warbled or whistled motifs, each one usually repeated 2–4 times; repetitive pattern makes song somewhat reminiscent of that of a mockingbird (Mimus). Calls include sharp “check” and “chuip” notes for contact.

Season May–Sept. Nests solitarily. Co-operative breeder, groups of 4–5 individuals attending nest or fledglings; also one adult, perhaps a breeding female, was fed by other adults from a nesting group. Nest built by several members of group, described as an open cup made from diverse plant material, two built mostly with dry leaves and branchlets of Chusquea tesellata bamboo, stems of Pennisetum clandestinum grass and dry branchlets of Miconia, external walls may include Usnea lichens, lining materials included thin fern stems and palm or bromeliad fibres, external nest diameter 25–30 cm, depth 16·5 cm, internal diameter 10–11 cm; placed mostly in oak, sometimes in Escallonia paniculata or Clethra, usually 5–10 m above ground, often on inaccessible external branch or above steep slope, some nests more or less camouflaged by arboreal leaf litter. No information on clutch size, eggshell fragments were pale blue with reddish-brown marks; no information on incubation and nestling periods; chicks fed by several group-members.

ENDANGERED. Restricted-range species: present in Colombian East Andes EBA. Rare and extremely local. Estimates of global population range from 1000 to 3000 individuals. Range formerly much wider, probably extending also to E slope. During 20th century this species was extirpated from many areas, and now has a patchy distribution. Habitat loss the main threat, as at least 80% of montane oak forests have been logged or converted to pasture. In recent surveys recorded at 22 localities, from Suratá (in Santander) S to La Aguadita (Cundinamarca), but follow-up surveys revealed that many of these were suffering rapid deforestation. During surveys in 2003–2006 in Serranía de los Yariguíes (a spur extending from main E Andean range in Santander) found at three sites, at one of which considered abundant. Yariguíes massif, a steep, forested range c. 100 km in length, still retains considerable amount of forest at elevations suitable for this icterid, and in Jan 2011 new population discovered at Reserva Páramo La Floresta (privately owned reserve administered by municipality of Zapatoca); this site, at elevation of c. 2600 m, includes second growth, sub-páramo, fragments of oak forest and, importantly, a humedal (marshy wetland), around which this icterid was the most conspicuous (and possibly most numerous) bird species. Very similar habitats exist elsewhere in Yariguíes range, but on isolated plateaux of steep forested mountains, and thus very difficult to reach; likely that these, too, support significant populations of this species. It is suggested that the Yariguíes population may comprise more than 800 individuals (2 Fundación ProAves de Colombia (2011). Notes on the status of various threatened birds species occurring in Colombia. Conservación Colombiana. 15: 22-28. Close ). In rest of this species’ range, population small and severely fragmented, and prospects for survival uncertain. Total population estimated at fewer than 2500 mature individuals (3 Renjifo, L. M., M. F. Gómez, J. Velásquez-Tibatá, A. M. Amaya-Villarreal, G. H. Kattan, J. D. Amaya-Espinel, and J. Burbano-Girón, Editors (2014). Libro Rojo de Aves de Colombia, Volume I: bosques húmedos de los Andes y la costa Pacífica. Editorial Pontificia Universidad Javeriana & Instituto Alexander von Humboldt, Bogotá D.C., Colombia. Close ). Conservation efforts and ecological studies at Guanentá–Alto Río Fonce Fauna and Flora Sanctuary, in Santander, and at Soatá and Tipacoque, in Boyacá, appear to have had some success and are continuing. In addition to Reserva Páramo La Floresta and Serranía de los Yariguíes National Park, reported from Las Orquídeas, Cueva de los Guácharos and Tatamá National Park, and from Ucumarí Regional Park. In Colombia, formerly considered Critically Endangered (4 Renjifo, L. M., A. M. Franco-Maya, J. D. Amaya-Espinel, G. H. Kattan, and B. López-Lanús (Editors) (2002). Libro Rojo de Aves de Colombia. Serie Libros Rojos de Especies Amenazadas de Colombia. Instituto de Investigación de Recursos Biológicos Alexander von Humboldt & Ministerio del Medio Ambiente, Bogotá, Colombia. Close ), but now assessed as Endangered at the national level (3 Renjifo, L. M., M. F. Gómez, J. Velásquez-Tibatá, A. M. Amaya-Villarreal, G. H. Kattan, J. D. Amaya-Espinel, and J. Burbano-Girón, Editors (2014). Libro Rojo de Aves de Colombia, Volume I: bosques húmedos de los Andes y la costa Pacífica. Editorial Pontificia Universidad Javeriana & Instituto Alexander von Humboldt, Bogotá D.C., Colombia. Close ).