Andean Avocet

This elegant and striking shorebird possesses a highly specialized morphology adapted to high-altitude aquatic ecosystems. It reaches a length of approximately 43 to 48 centimeters. Its most diagnostic feature is its long, thin, and prominently upturned black bill, which is perfectly adapted for sweeping muddy substrates. The bird features a highly contrasting plumage, with pure white coloring its head, neck, mantle, underparts, and rump, while its back, wings, and tail exhibit a deep blackish-brown to jet-black tone. Unlike other members of its genus, this species lacks distinct seasonal plumage variations and does not display pronounced sexual dimorphism. Notably, its eyes feature a striking bright yellow or orange iris, a unique anatomical trait among its closest relatives. Its long, slender legs are of a pale blue-gray coloration, equipped with partially webbed feet that allow it to navigate soft, muddy terrains without sinking.

Geographical distribution: This high-altitude specialist is restricted to the Central Andes of South America. Its range encompasses the montane plateaus of southern Peru, western Bolivia, northern Chile (particularly the regions of Parinacota, Tarapacá, and Antofagasta), and northwestern Argentina (including the provinces of Jujuy, Salta, Catamarca, and Tucumán).

Habitat: It is almost exclusively found in high-elevation wetlands, typically at altitudes ranging between 3,100 and 4,500 meters above sea level. Its preferred environments include saline and hypersaline lakes, brackish lagoons, high-Andean peatlands known as bofedales, and shallow seasonal wetlands. It thrives in highly alkaline and saline water bodies where terrestrial vegetation is sparse, consisting mainly of low-growing halophytic shrubs and tough bunchgrasses.

Feeding: This bird feeds predominantly on small aquatic invertebrates found within muddy sediments or suspended in the water column. Its diet consists of micro-crustaceans (such as Artemia), dipteran insect larvae, tiny mollusks, and occasionally aquatic plant seeds and diatoms. While foraging, it walks slowly through shallow waters, utilizing a characteristic lateral scythe-like sweeping motion of its upturned bill to filter organic matter and prey from the soft substrate.

Behavior: It is a social species, often forming loose, quiet flocks of 10 to 100 individuals, and is frequently seen foraging alongside Andean and James’s flamingos. It is primarily a resident bird, although it performs altitudinal migrations to lower valleys during harsh winter periods when the high-altitude Andean lagoons freeze over. Its vocalizations are remarkably quiet compared to other avocets, emitting soft, low-pitched whistling calls when disturbed or during flight.

Nesting: The breeding season takes place during the dry season and early southern spring, running from September to January. It breeds in loose, semi-colonial aggregations on dry mudflats, sandy shores, or salt crusts near the water´s edge. The nest is a shallow, unlined scrape in the ground, occasionally decorated with small pebbles, salt crystals, or bits of dry vegetation. A typical clutch consists of 3 to 4 olive-colored eggs heavily speckled with dark brown and black markings, which provide exceptional camouflage. Both male and female adults share incubation duties and actively defend the nesting territory against potential intruders.

Conservation status: It is currently classified as Least Concern (LC) on the IUCN Red List of Threatened Species. Although its global population is considered stable, its highly localized and fragile habitat is increasingly threatened by climate change, water diversion for lithium mining projects, and agricultural activities that lead to the degradation of delicate Andean wetland ecosystems.