Cat-Like Stinker

Thursday, January 23, 2025

Cat-Like Stinker

Today’s special animal friend is the fossa, Cryptoprocta ferox, a carnivore unique to Madagascar. The fossa belongs to the family Eupleridae, which includes all carnivores in Madagascar. Biologists believe that carnivores colonized Madagascar only once, around 18-20 million years ago. The Eupleridae belong to the “more like a cat” suborder Feliformia, but this was disputed by biologists for many years. The fossa looks like a puma crossed with a weasel or mongoose.

Their head-body length is about 30 inches and their tail an inch or two shorter. Adult males weigh a little more than females. Their short fur is reddish brown on the back, light tan underneath. They have muscular limbs, flexible bodies, and very limber ankles. They climb and jump well, and captive juveniles have been observed swinging from ropes by their back feet. They produce many different bodily secretions and basically reek.

Fossa are found throughout Madagascar in forested areas. They prefer undisturbed forests with higher humidity but can survive in dry and thorny forests and those with some disruption. They are the primary predator of lemurs, which make up around 50% of their diet. Other prey include rodents, reptiles, birds, and invertebrates. They can capture prey nearly as large as themselves and have been observed hunting cooperatively and sharing the kill. They are active both day and night — “cathemeral” — and hunt both on the ground and in the trees.

Fossa have unusual genitalia. I don’t usually go into detail about these things, but, in this case, one must. The male fossa has an unusually long penis and penis bone. When erect, it reaches to between his front legs. About half the length is covered with the spiny glans. Females, on the other hand, experience “masculinization” from about a year old to four years old. The female develops an enlarged, spiny clitoris and produces secretions resembling those from a male’s genitals. Scientists speculate that this feature confuses males, deterring sexual harassment or assault of immature females. Another possibility is that it confuses older females, protecting the younger ones from territorial aggression.

Fossa mating habits are unusual as well. Females are polyandrous, like some cats. A fertile female will rest on a horizontal branch over 60 feet off the ground. Multiple males are attracted by her scent and calls. They will compete with vocalizations and physical aggression for the privilege of climbing the tree and trying their luck. Scientists do not know what criteria female fossas use to accept or reject a mate. One female may mate with several males and then leave the spot to another female. This procedure maximizes the mating opportunities for this solitary and widely dispersed species.

Two to four young are the usual litter. The newborns are tiny and very fragile. They leave their birth den after about 4-1/2 months and remain in the care of their mother for about a year. Lifespan is about 20 years in captivity.