The Andean mountain cat has an ashy-gray fur, a gray head, ears and face. The areas around the lips and cheeks are white; two dark brown lines run from the corners of the eyes across the cheeks. There are some black spots on the forelegs, yellowish-brown blotches on the flanks, and up to two narrow, dark rings on the hind limbs. The long bushy tail has 6–9 rings, which are dark brown to black. The markings of juveniles are darker and smaller than of adults. The skulls of adult specimens range in length from 100.4 to 114.8 mm (3.95 to 4.52 in) and are larger than of pampas cat and domestic cat.
The Andean mountain cat has a black nose and lips, and rounded ears. On the back and on the tail, the hair is 40–45 mm (1.6–1.8 in) long. Its rounded footprints are 4 cm (1.6 in) long and 3.5 cm (1.4 in) wide. Its pads are covered with hair.
Adult specimens range from 57.7 to 85 cm (22.7 to 33.5 in) in head-to-body length, with a 41.3 to 48.5 cm (16.3 to 19.1 in) long tail. The shoulder height is about 36 cm (14 in) and body weight is up to 5.5 kilograms (12 lb).
The Andean mountain cat and pampas cat look similar. This makes it difficult to identify which cat is observed and makes correct estimations of populations problematic. This can be especially difficult when attempting to gain correct information from the observations of individuals that have seen one of these cats but are not aware to look for specific features to distinguish between the two.
Andean mountain cats occur only at high elevations in the Andes. Records in Argentina indicate that they live at elevations from 1,800 m (5,900 ft) in the southern Andes to over 4,000 m (13,000 ft) in Chile, Bolivia and central Peru. This terrain is arid, sparsely vegetated, rocky and steep. The population in the Salar de Surire Natural Monument was estimated at five individuals in an area of 250 km2 (97 sq mi). Results of a survey in the Jujuy Province of northwestern Argentina indicates a density of seven to 12 individuals per 100 km2 (39 sq mi) at an elevation of about 4,200 m (13,800 ft).
Andean mountain cats occur localized. Their habitat in the Andes is fragmented by deep valleys, and their preferred prey, mountain viscachas (Lagidium) occur in patchy colonies. Across this range, the level of genetic diversity is very low.
While the Andean mountain cat's main prey is likely the mountain viscacha, it is also probable that mountain chinchillas were previously important prey of the Andean mountain cat before their populations were drastically reduced due to hunting for the fur trade. Since it lives only in the high mountains, human-inhabited valleys act as barriers, fragmenting the population, meaning that even low levels of poaching could be devastating. They are often killed in Chile and Bolivia because of local superstition.
Six different species of carnivores live in the Andes Mountain range. Three of these species are cats, the Andean cat, the pampas cat, and the puma. The puma is a large predator, while the Andean and Pampas Cat are medium-sized predators. These two medium-sized predators are very much alike. They both hunt within the same territory. They hunt the same prey, the mountain viscacha (Lagidium viscacia). The viscacha makes up 93.9% of the biomass consumed in the Andean cat's diet while the Pampas Cat depends on it for 74.8% of its biomass consumption. Both of these cats depend on a specific prey to make up a large portion of their dietary needs. In some areas, the mountain viscacha will make up 53% of the Andean cat's prey items. This is because the other prey items are so significantly smaller that even though the Andean cat will successfully hunt, kill, and eat a mountain viscacha half the time, the mountain viscacha is so much larger than the other food items, it makes up more substance. They also hunt frequently during the same periods. During one study, both the Andean cat and the Pampas Cat were seen most frequently during moonless nights; the second most sightings of these cats were during full moons. These two cats both hunt the same prey, making it more difficult for them to find food, essentially creating a race to find the prey before the other does.
By using the residents' observations of Andean cats in coupled pairs with their litters, it is theorized that the mating season for the Andean cat is within the months of July and August. Because kittens have been seen in the months of April and October, this could mean that the mating season extends into November or even December. A litter will usually consist of one or two offspring born in the spring and summer months. This is common with many other species that also have their young when food resources are increasing.
In 2002 the status of the Andean cat was moved from Vulnerable to Endangered on the IUCN Red List. Due to the Andean cat's habitat being spread across four countries, biologists have attempted to collaborate in efforts to protect the species. One of the groups formed was the Andean Cat Conservation Committee, now known as the Andean Cat Alliance. The table below was taken directly from the most current strategy plan for 2011-2016.
The Andean cat's habitat spans four different South American countries. Each country has made individual laws to protect this wild cat. Each country also has its own protected game areas where hunting is prohibited. The table below outlines the number of the protected areas that fall within the Andean cat's habitat. Biologists are attempting to determine if any of these protected areas house significant populations of Andean cats.
Prior to 1998, the only evidence of this cat's existence was two photographs. It was then that Jim Sanderson took up his quest to find the Andean mountain cat. Sanderson sighted and photographed one in Chile in 1998 near Chile's northern border with Peru. In 2004, he joined a Bolivian research team and helped radio-collar an Andean cat in Bolivia. In April 2005, this cat was found dead, perhaps after being caught in a poacher's trap.
Sanderson is still involved with the Andean cat. Together with Constanza Napolitano, Lilian Villalba, and Eliseo Delgado and others in the Andean Cat Alliance, the Small Cat Conservation Alliance has forged conservation agreements with Fundación Biodiversitas, a Chilean non-profit organization, and CONAF, the government agency responsible for managing national parks and production forests. CONAF has agreed to allow the SCCA to renovate a building for the Andean Cat Conservation and Monitoring Center on their already-functioning compound at San Pedro de Atacama in Chile.
Villalba of the Andean Cat Alliance conducted a major research program, including radio-telemetry studies, from 2001 to 2006 in the Khastor region of southern Bolivia.
Conservation efforts are also being made by the Feline Conservation Federation to preserve this species.