The Guanaco (Lama guanicoe) is a camelid native to South America, closely related to the llama. Guanacos are one of two wild South American camelids, the other being the vicuña, which lives at higher elevations.

The guanaco gets its name from the Quechua word huanaco (modern spelling wanaku). Young guanacos are called chulengos.

Guanacos stand between 1.0 and 1.3 m (3 ft 3 in and 4 ft 3 in) at the shoulder, body length of 2.1 to 2.2 m (6 ft 11 in to 7 ft 3 in), and weigh 90 to 140 kg (200 to 310 lb). Their color varies very little (unlike the domestic llama), ranging from a light brown to dark cinnamon and shading to white underneath. Guanacos have grey faces and small, straight ears. The lifespan of a guanaco can be as long as 28 years.

Guanacos are one of the largest terrestrial mammals native to South America today.[8] Other terrestrial mammalian megafauna weighing as much or more than the guanaco include the tapirs, the marsh deer, the white-tailed deer, the spectacled bear, and the jaguar.

Guanacos have thick skin on their necks, a trait also found in their domestic counterparts, the llama, and their relatives, the wild vicuña and domesticated alpaca. This protects their necks from predator attacks. Bolivians use the neck skin of these animals to make shoes, flattening and pounding the skin to be used for the soles. In Chile, hunting is allowed only in Tierra del Fuego, where the only population not classified as endangered in the country resides. Between 2007 and 2012, 13,200 guanacos were legally hunted in Tierra del Fuego.

Like all camels, Guanacos are herbivores, grazing on grasses, shrubs, herbs, lichens, fungi, cacti, and flowers. The food is swallowed with little chewing and first enters the forestomach to be digested finally after rumination. This process is similar to that of ruminants, to which camels are not zoologically related. The camels' digestive system is likely to have developed independently of ruminants, which is evidenced by the fact that the forestomachs are equipped with glands.

Guanacos are often found at high altitudes, up to 4,000 m (13,000 ft) above sea level, except in Patagonia, where the southerly latitude means ice covers the vegetation at these altitudes. For guanacos to survive in the low oxygen levels found at these high altitudes, their blood is rich in red blood cells. A teaspoon of guanaco blood contains about 68 million red blood cells; four times that of a human.

Guanaco fiber is particularly prized for its soft, warm feel and is found in luxury fabric. In South America, the guanaco's soft wool is valued second only to that of vicuña wool. The pelts, particularly from the calves, are sometimes used as a substitute for red fox pelts, because the texture is difficult to differentiate. Like their domestic descendant, the llama, the guanaco is double-coated with coarse guard hairs and a soft undercoat, the hairs of which are about 16–18 µ in diameter and comparable to cashmere.

Subspecies

• Lama guanicoe guanicoe

• Lama guanicoe cacsilensis

• Lama guanicoe voglii

• Lama guanicoe huanacus

Guanacos inhabit the steppes, scrublands and mountainous regions of South America. They are found in the altiplano of Peru, Bolivia and Chile, and in Patagonia, with a small population in Paraguay. In Argentina they are more numerous in Patagonian regions, as well as in places such as Isla Grande de Tierra del Fuego. In these areas, they have more robust populations, since grazing competition from livestock is limited. Guanaco responded to forage availability, occupying zones with low to intermediate food availability in the breeding season, and those with the highest availability in the non-breeding season.

Estimates, as of 2016, place their numbers around 1.5 to 2 million animals 1,225,000–1,890,000 in Argentina, 270,000–299,000 in Chile, 3,000 in Peru, 150–200 in Bolivia and 20–100 in Paraguay. This is only 3–7% of the guanaco population before the arrival of the Spanish conquistadors in South America. A small population introduced by John Hamilton exists on Staats Island in the Falkland Islands (Malvinas), with a population of around 400 as of 2003. In Torres del Paine National Park, the numbers of Guanacos increased from 175 in 1975 to 3,000 in 1993.

Guanacos live in herds composed of females, their young, and a dominant male. Bachelor males form separate herds. While reproductive groups tend to remain small, often containing no more than 10 adults, bachelor herds may contain as many as 50 males. When they feel threatened, guanacos alert the herd to flee with a high-pitched, bleating call. The male usually runs behind the herd to defend them. They can run at 56 km/h (35 mph) per hour, often over steep and rocky terrain. They are also excellent swimmers. A guanaco's typical lifespan is 20 to 25 years.

Atacama Desert

Some guanacos live in the Atacama Desert, where in some areas it has not rained for over 50 years. A mountainous coastline running parallel to the desert enables them to survive in what are called "fog oases" or lomas. Where the cool water touches the hotter land, the air above the desert is cooled, creating a fog and thus, water vapor. Winds carry the fog across the desert, where cacti catch the water droplets and lichens that cling to the cacti soak it in like a sponge. Guanacos then eat the cacti flowers and the lichens.