Cryptoprocta Ferox (Fossa)

The Fossa (Cryptoprocta ferox) is a cat-like, carnivorous mammal endemic to Madagascar. It is a member of the Eupleridae, a family of carnivorans closely related to the mongoose family (Herpestidae). Its classification has been controversial because its physical traits resemble those of cats, yet other traits suggest a close relationship with viverrids (most civets and their relatives). Its classification, along with that of the other Malagasy carnivores, influenced hypotheses about how many times mammalian carnivores have colonized Madagascar. With genetic studies demonstrating that the fossa and all other Malagasy carnivores are most closely related to each other (forming a clade, recognized as the family Eupleridae), carnivorans are now thought to have colonized the island once around 18 to 20 million years ago.

Physical Description

The fossa is the largest mammalian carnivore on the island of Madagascar and has been compared to a small cougar. Fossas are cat-like in appearance, with blunt noses and large, forward-facing eyes. Total body length ranges from 610 to 800 mm, with a tail of matching length. Shoulder height is typically 370 mm. Fossas have vibrissae that are as long as their heads, and are covered in short, thick fur of a reddish-brown color, although there are sometimes black individuals. They have short, curved, retractile claws (meaning it can extend but not retract its claws fully) and a plantigrade stance. Anal and preputial glands can be found. Males have a large baculum, a barb on the glans of the penis, and are slightly larger than females. They have rounded ears. Teeth are shorter and fewer in number (32 to 36) than other viverrids. The generic name, Cryptoprocta, comes from the fact that the anus ("procta") is hidden ("crypto") by an anal pouch.

Habitat and distribution

The fossa has the most widespread geographical range of the Malagasy carnivores, and is generally found in low numbers throughout the island in remaining tracts of forest, preferring pristine undisturbed forest habitat. It is also encountered in some degraded forests, but in lower numbers. Although the fossa is found in all known forest habitats throughout Madagascar, including the western, dry deciduous forests, the eastern rainforests, and the southern spiny forests, it is seen more frequently in humid than in dry forests. This may be because the reduced canopy in dry forests provides less shade, and also because the fossa seems to travel more easily in humid forests. It is absent from areas with the heaviest habitat disturbance and, like most of Madagascar's fauna, from the central high plateau of the country.

The fossa has been found across several different elevational gradients in undisturbed portions of protected areas throughout Madagascar. In the Réserve Naturelle Intégrale d'Andringitra, evidence of the fossa has been reported at four different sites ranging from 810 to 1,625 m (2,657 to 5,331 ft). Its highest known occurrence was reported at 2,000 m (6,600 ft); its presence high on the Andringitra Massif was subsequently confirmed in 1996. Similarly, evidence has been reported of the fossa at the elevational extremes of 440 m (1,440 ft) and 1,875 m (6,152 ft) in the Andohahela National Park. The presence of the fossa at these locations indicates its ability to adapt to various elevations, consistent with its reported distribution in all Madagascar forest types.

Food Habits

Fossas are the largest mammalian carnivores on the island of Madagascar. Their diet consists of small mammals, birds, reptiles, amphibians, and insects. Fossas also prey on lemurs (Lemuridae). They are excellent climbers and will pursue lemurs through the trees. Over 50% of its diet consists of lemurs, the endemic primates found on the island; tenrecs, rodents, lizards, birds, and other animals are also documented as prey.

Reproduction

Aggression among males may occur during the mating season, including threatening calls and postures, which lead to fights where each contestant tries to bite the other. Copulation can occur on the ground or on a horizontal branch. To signify her readiness to mate, the female lifts her hindquarters and turns her external genitalia inside out about two to three centimeters. The male then mounts her and bites the back of her neck. The period of copulation lasts up to 165 minutes.

Mating occurs in September and October, and young are born in a den in December and January after a three month gestation period. At birth the two to four young weigh 100 grams each. They are altricial, being toothless and blind, but furred. At four and a half months a young fossa is weaned and ventures out of the den. The young fossa leaves its mother when it reaches fifteen to twenty months of age, have adult teeth at 2 years old and attain full adult size at four years of age

Justification (IUCN Red List)

The fossa is listed as "Vulnerable" by the International Union for Conservation of Nature. It is generally feared by the Malagasy people and is often protected by their fady (taboo). The greatest threat to the species is habitat destruction.