Upland Goose

Exhibits pronounced sexual dimorphism and stands as one of the most representative waterfowl species of the southern cone of South America, characterized by a robust skeletal structure, a body length ranging from 60 to 72 centimeters, and a body mass between 2.7 and 3.5 kilograms. The male features a pristine white plumage on the head, neck, and breast, contrasting with a delicate black barring across the upper back and flanks. Two distinct color morphs occur in males: the barred morph, which displays dark banding across the entire underparts, and the white-breasted morph, typical of the insular subspecies Chloephaga picta leucoptera, which has an entirely white belly. Conversely, the female displays a warm cinnamon-brown coloration with heavy black barring on the breast and flanks, providing excellent camouflage against terrestrial predators in its nesting grounds. Both sexes possess a short, strong black bill, but their leg coloration differs dramatically: males have dark slate-grey or blackish legs, whereas females have bright orange-yellow legs.

Geographical distribution: Occupies the southernmost regions of South America, with a vast breeding range spanning the Patagonian regions of Chile and Argentina, the Tierra del Fuego archipelago, and the Falkland Islands. During the austral summer, continental populations aggregate in these southern latitudes to breed. With the onset of autumn, these mainland populations undertake an extensive northward migration, wintering across the vast pampean plains of central Argentina, including the provinces of Buenos Aires, La Pampa, and southern Córdoba, as well as the central valleys of Chile. In contrast, the larger subspecies Chloephaga picta leucoptera is entirely sedentary, remaining as a year-round resident throughout the Falkland Islands without performing long-distance migrations.

Habitat: Prefers open, low-altitude terrestrial ecosystems, showing a strong affinity for shrubby steppes, damp peatlands known as mallines, flooded pastures, and the semi-arid grasslands of the Patagonian steppe. It has adapted successfully to human-modified landscapes, frequently utilizing agricultural fields, artificial pastures for sheep ranching, and cleared areas near rural settlements. During the breeding season, its presence is strictly tied to freshwater bodies, such as riverbanks, streams, freshwater lakes, and temporary lagoons, which offer safe havens and rich foraging grounds. During migration and wintering, it also utilizes coastal salt marshes, estuarine mudflats, and harvested crop fields.

Feeding: Maintains an strictly herbivorous diet, with a specialized digestive tract designed to process large quantities of fibrous vegetation. Its foraging strategy consists of continuous grazing on grasses, tender shoots, herbaceous leaves, roots, tubers, and seeds extracted directly from the ground. Its primary food sources belong to the Poaceae and Cyperaceae families. Seasonally, it supplements its nutrient intake with wild berries and seeds native to the Patagonian scrublands. Due to its preference for short, highly nutritional grass, it often feeds alongside livestock, utilizing pastures kept short by sheep or cattle grazing, which exposes the most succulent basal parts of the vegetation.

Behavior: Demonstrates highly gregarious habits outside the breeding season, forming massive flocks of hundreds or even thousands of individuals that forage and roost collectively to maximize predator detection. This social behavior changes drastically at the start of the austral spring, when breeding pairs isolate themselves and become intensely territorial. They defend their nesting territories through aggressive physical displays and loud, sexually dimorphic vocalizations: males emit a high-pitched, metallic whistle, while females produce a low, harsh, cackling grunt. Although strong and capable fliers, they prefer terrestrial locomotion, running or swimming when threatened, especially during the post-breeding molt when they shed their flight feathers and become temporarily flightless.

Nesting: Commences during the austral spring and summer, typically stretching from October to January. The female selects a well-concealed site on the ground, usually hidden within tall tussocks of grass, thorny bushes, or rocky crevices near freshwater shorelines. The nest is a shallow scrape lined with dry grasses, leaves, and a dense layer of soft down feathers plucked from the female´s own breast. She lays a clutch of 5 to 8 creamy-white eggs, which she incubates exclusively for approximately 30 days. During this period, the male remains vigilant nearby, aggressively defending the territory against intruders. The precocial chicks hatch covered in down and leave the nest within hours, guided by both parents to safe foraging areas, eventually fledging and reaching independence at around 70 days of age.

Conservation status: Classified as Least Concern (LC) on the IUCN Red List of Threatened Species, reflecting its extensive geographical range and overall stable global populations, particularly those residing in the Falkland Islands. However, mainland populations wintering in central Argentina have experienced historical declines due to habitat fragmentation driven by agricultural expansion, illegal hunting, and persecution by ranchers who view them as competitors for sheep pastures. Current conservation initiatives and local game regulations aim to mitigate these human-wildlife conflicts and protect key breeding and wintering habitats across Patagonia.