Black-necked woodpecker

The black-necked woodpecker (Colaptes atricollis), also known as the black-necked flicker, is a species of bird endemic to Peru. It belongs to the woodpecker family Picidae and is recognized by its distinct plumage, particularly the differences between males and females on their heads. This species is found in a variety of semi-arid to arid landscapes across the Peruvian Andes.

Description and Identification

Adult black-necked woodpeckers measure between 26 to 27 cm in length and typically weigh between 73 to 90 grams. Males and females share similar plumage, with the most notable differences occurring on their heads. Adult males of the nominate subspecies feature dark gray from the forehead to the forecrown, with red on the hindcrown and upper nape, often with red feather tips in the gray areas. Their lores, eye area, and nape are yellowish white, bordered below by a red malar stripe, and they possess a black chin and throat. Adult females, in contrast, have red only on the hindcrown, and their malar stripe is blackish. Both sexes display bronze-green upperparts marked with narrow blackish bars, which become paler on the rump and uppertail coverts. Their flight feathers are dark brown with yellowish barring and olive-yellow shafts. The tail is dark brown, with the central feathers and the outer web of the outermost pair exhibiting paler barring. The breast is black, and the rest of the underparts are pale yellow with black bars. Their bill is longish and black with a paler base, their iris is brown to chestnut-brown, and their legs are green-gray. Juveniles are generally duller than adults, with darker faces and often red on the top of their head with dark bars, a mixed black and red malar, and more diffuse barring on both upper and underparts. The subspecies C. a. peruvianus is noted to be smaller than the nominate subspecies, with a shorter bill, paler upperparts that are more heavily barred, and less-barred, paler underparts.

Distribution and Habitat

The black-necked woodpecker is found exclusively in Peru. The nominate subspecies, C. a. atricollis, inhabits the west slope of the Peruvian Andes, ranging from the departments of La Libertad to Tacna. The subspecies C. a. peruvianus is distributed on the east slope of Peru's Andes, extending from the Marañón River valley southward into the Huánuco Department. The species is adaptable to a range of environments, including drier cloud forests, montane scrublands interspersed with cacti, desert scrublands, and deciduous woodlands. It also readily occupies riparian woodlands, orchards, plantations, and gardens. Elevations at which it is found vary, typically between 500 and 2,800 meters on the western slope, though it can be found as high as 4,000 meters. In the Marañón Valley, it is observed between 1,700 and 4,300 meters.

Behavior and Ecology

Movement

The black-necked woodpecker is largely a year-round resident throughout its established range, although some seasonal movements related to elevation are suspected.

Feeding

This woodpecker's diet is overwhelmingly composed of ants, consuming both adult ants and their various life stages, including larvae and pupae. Foraging typically occurs singly or in pairs, and the birds forage at all vertical levels, from the ground up to the highest branches of trees. Their primary methods of capturing food involve gleaning insects from surfaces and probing into crevices.

Breeding

The breeding season for the black-necked woodpecker is not precisely defined but appears to be concentrated around the months of June and July. Nesting sites have been documented in a variety of structures, including natural tree cavities, cacti, artificial utility poles, and even in the bank of a dry river. A clutch typically consists of two to four eggs. The incubation period lasts for approximately 14 days, and the young fledge about 28 days after hatching. Both adult males and females share the responsibilities of incubating the eggs and providing nourishment to the nestlings.

Vocalization

The characteristic vocalizations of the black-necked woodpecker include a distinct, "loud clear 'wic' in [a] long series." Alarm calls have been described as "peah" and "chypp."

Conservation Status

The International Union for Conservation of Nature (IUCN) has assessed the black-necked woodpecker as being of Least Concern. The species possesses a broad geographic range, and while its exact population size is not precisely known, it is believed to be stable. No significant immediate threats have been identified that would jeopardize its long-term survival. The species is generally considered uncommon, though it can be locally more abundant in certain areas.