Fossa

Quick Take

• Despite looking like a cat and acting like one, the fossa is actually related to a completely different animal, a fact that fooled scientists for years. Explore its true ancestry →
• The fossa can grow nearly 6 feet long, yet an extinct relative dwarfed it entirely. This hints that Madagascar once harbored something far more formidable. Meet the Giant Fossa →
• The fossa is Madagascar's apex predator with no natural enemies, so it raises the question of why fewer than 2,500 remain in the wild. See the population crisis →
• The fossa rests in a place most animals would never choose, and the reason behind this choice turns out to reveal a lot about how it survives. Discover its resting habits →

The fossa (Cryptoprocta ferox) is a slender, cat-like carnivore found only in Madagascar. It is the largest meat-eating mammal on the island and feeds mostly on lemurs. Because it depends on the island’s forests, the fossa is listed as Vulnerable by the IUCN.

Classification And Evolution

The Fossa is a medium-sized, carnivorous animal that is found on the island of Madagascar. The Fossa belongs to the group of Malagasy Carnivores, which are thought to have descended from Mongoose-like ancestors that arrived in Madagascar from Africa between 18 and 24 million years ago. Not only is it one of the most ancient of the ten species found on the island but it is also the largest. Due to its cat-like appearance, until recently, it was believed to be a primitive species of feline. Unfortunately, like many of the unique animal species found in Madagascar, the Fossa is incredibly rare and due to the loss of natural habitat is now considered to be endangered.

Anatomy And Appearance

The Fossa is the largest land predator on the island of Madagascar and some individuals of the species can grow to nearly 6 feet in length from their nose to the tip of their long and slim tails. The Fossa’s tail is around the same length as its body and plays a vital role in helping them balance as they leap through the trees. The Fossa is an animal with short but dense red to dark brown fur, a small cat-like head, a dog-like snout, large forward-facing eyes, and small, rounded ears. In spite of being related to Mongooses, the Fossa has quite a number of feline features including curved, retractable claws and slightly webbed feet which both help when it is moving about amongst the branches.

Distribution And Habitat

Like the majority of plant and animal species found in Madagascar, the Fossa is an animal that is found nowhere else in the world. They rely on dense forested areas with an ample food source and plenty of space to establish a large territory. Historically, Fossas were found in woodland and forested areas across the island from coastal lowlands to mountainous regions, but due to extensive deforestation throughout Madagascar they are now restricted to a tiny portion of their once vast natural range. Growing human populations have also severely affected Madagascar’s Fossa numbers as they are often hunted by farmers who fear for their livestock.

Behavior And Lifestyle

The Fossa is a nocturnal mammal, preferring to be alone, that patrols territories as large as 26 square kilometers (10 square miles) and marks its presence with scent released from its large anal gland. The vast majority of the fossa’s life is spent high in the trees, but it is also known to move about and hunt on the ground. They are incredibly agile at both climbing and leaping, which is largely aided by their long and slender tail and moving on the flat soles of their feet gives them greater balance and stability when landing on branches. Although the Fossa is largely nocturnal, they are known to also hunt during the day, especially when they lack food, but prefer to spend the daylight hours resting in a hollow tree, cave, or an abandoned termite mound.

Reproduction And Life Cycles

Fossas, similar to other solitary carnivores, come together only to mate. Their breeding season is generally in September and October. With a gestation period that lasts around three months, the female will normally give birth to two to four cubs. The cubs are very underdeveloped at birth and don’t open their eyes until they are between two and three weeks old. The young are cared for by their mother and begin to eat solid foods around 12 weeks old, although it takes another month until they are weaned. It takes almost two years for young fossas to grow to their adult size and another two years until they are able to reproduce. They can live for up to 17 years although many reach much younger ages.

Diet And Prey

The largest carnivorous mammal on Madagascar, the fossa survives by eating other animals in the surrounding area and has evolved to be the perfect hunter of lemurs, a staple of their diet. More than half of the Fossa’s diet is comprised of lemurs. They will also eat lizards, birds, rodents, frogs, and reptiles to supplement their diet along with small domestic animals like pigs and poultry. By hunting at night, the dark coat of the Fossa is perfectly camouflaged into the thick surrounding forest so they are able to stalk their prey quietly in the trees before leaping powerfully to capture it. The retractable claws of the Fossa mean that they are always at their sharpest for catching prey as they are not being dulled by being constantly walked on.

Predators And Threats

Because the Fossa is the largest natural predator in Madagascar, it has no predators itself (with perhaps the rare exception of being grabbed by a stray Crocodile). Humans pose the biggest threat to the Fossa for they have not only hunted them in order to protect their livestock but they have also obliterated between 80 and 90% of the Fossa’s once vast natural range. Deforestation due to logging for rare tropical timber and for clearing of land for agriculture has led to extensive declines in the wild population numbers. Coupled with the fact that Fossas require large solitary home ranges and are relatively slow at developing, their numbers will most likely continue to decline.

Interesting Facts And Features

The Fossa usually measures around 3 feet long with the same length tail on top of that but, more recently, fossils of the now-extinct Giant Fossa have been uncovered in Madagascar, with the species, known as Cryptoprocta spelea, estimated to have been roughly 1.5 to 2 times larger than the modern fossa, which itself reaches about 4.6 to 6 feet in total length. As the Fossa is well known for its dominant and fierce approach to hunting, it is extremely rare that its intended prey will successfully escape. The Fossa is unbelievably fast and incredibly agile in the tree tops so once a meal has been spotted, it is very accomplished at catching it.

Relationship With Humans

When early explorers first arrived on Madagascar, most of the incredible variety of unique fauna and flora they would have seen is most likely no longer in existence. Since their first arrival, humans have been exploiting one of the world’s largest islands leaving just 10% of the tropical forest cover. Land clearance for agriculture, including palm oil plantations, and deforestation of the unique tropical trees has led to drastic declines in the population of a multitude of species, including the unique Fossa.

Conservation Status And Life Today

The Fossa is currently listed by the IUCN as an Vulnerable species and at risk of becoming extinct in the near future in its natural environment. There are National parks and reserves on the island, but they are not large enough to ensure the Fossa population’s survival, as each individual requires a significantly large territory and faces too much competition. It is estimated that there are fewer than 2,500 Fossas left in the wild of Madagascar.