Gregarious, defensive and territorial: it’s no wonder the Upland Goose (or Magellan Goose, Chloephaga picta) is a noticeable presence across southern mainland South America. You’ll see Upland Geese gather at abundant food sources in staggering numbers. Their competition? Historically, it’s been local sheep and cows. As such, farmers have considered them a pest, though we welcome the sights and sounds of these ubiquitous flocks.
The most common subspecies of Upland Goose in the southern cone has a white head, neck, breast and belly with black, white and metallic green wings, distinguishing it from the subspecies found further east on the Falkland Islands. Additionally, the sexes differ in both plumage and coloring. Females are cinnamon-brown in color, patterned with heavy black barring and a glossy black tail, while males are more striking in contrasting shades of black and white. Males call out in repeated whistles (“whee whee!”) to which females respond with a low, raspy cackling (“har har harrrr!”).
The Upland Goose is well adapted to walking, running and feeding on land, given its upright stance and long, powerful legs. Growing up to 72 centimeters in length, this Goose is also characterized by vestigial webbing between its toes. On the mainland, northern breeders tend to remain in the same area year round, while the southern birds migrate north over the winter. Though the Upland Goose prefers to breed close to rivers and streams – or close to the ocean, in the case of the Falkland’s subspecies – it is not uncommon to spot geese far from water.
Found primarily in open grasslands, these diurnal grazers feed mostly on grass with berries, seeds and green algae as supplemental treats. While Upland Geese favor short grass for grazing, the birds generally breed in denser vegetation in order to conceal the nest. Mates are monogamous and extremely territorial; fights often result in injury and even death. Such defensive behavior is warranted, however, as infant mortality is high due to predation by birds of prey. Chicks leave the nest soon after hatching and never return, though they remain close to their parents, feeding on insects and vegetation.
The Upland Goose is thriving down in the park, despite the hunting and habitat destruction that are responsible for relative decline in numbers on the mainland. Though pesky to farmers in the region – resulting in the persecution of the species via destruction of eggs and shooting of adults – the resilient Upland Goose has maintained its status as one of the most prevalent birds in the region.