Makira Lessons: Why Do Fosa Eat Soap (Or, Euplerids Are Enigmas)

Originally published on Medium 11/23/16.

The fosa ( Cryptoprocta ferox ), Madagascar’s largest native predator, thinking about eating soap (probably).

The fosa (Cryptoprocta ferox), Madagascar’s largest native predator, thinking about eating soap (probably).

How would you feel about going on a spontaneous tropical cruise with a group of your closest friends? No planning, no talking it over, just getting up and sailing away. Nice, right? The catch here is that this cruise is a one-way journey that will take place on a mat of vegetation. There will be little food and water. A few of your friends will probably die. When you finally make landfall, hopefully you’re attracted to your remaining friends, because they are now your only dating options. Better throw on some Isleys or Marvin Gaye.

A similar cruise happened to a group of mongoose-like animals 19 to 26 million years ago. Due to a freak accident, these creatures sailed 200+ miles across the Mozambique Channel and landed on Madagascar [1].


Once they got there, they started doing what animals do best. The fruit of that labor are the ten species of carnivore present in Madagascar today.

Carnivores are cool, so they tend to be well-researched. Unfortunately, Madagascar’s equally cool lemur species overshadowed the carnivores. For a long time the most we knew was that the carnivores preferred forest to not-forest and that fosa occasionally came into camps to eat soap. Fast-forward to 2014 and Madagascar’s carnivores —the euplerids, which can be found nowhere else in the world — were some of the world’s most threatened but least studied carnivores [2]. The difficulties of doing research in Madagascar made studies few and far between.

The camera trap lies in wait for its prey.

The camera trap lies in wait for its prey.

With the recent popularity of camera traps, research became much easier and cheaper. Set up a camera on a tree and wait for an animal to step in front of it and get a candid taken. With a few pictures, you can figure out what species are present where, when they are active, and how they interact with other species.

Unlike the first mongooses to land on the island, our team of Virginia Tech and WCS researchers decided to be pioneers. No one had surveyed the carnivores in the Masoala-Makira forest complex.

Masoala-Makira is Madagascar’s largest area of protected forest.

Masoala-Makira is Madagascar’s largest area of protected forest.

What species were there? How were they dealing with forest loss? Would we get pictures of fosa eating soap? Our plan was simple. Haul action packers of camera traps and batteries to the northeast. Set them out in the forest. Wait for the hundreds of thousands of pictures to roll in.

What Did We Find?

That face when you realize someone is taking pictures of you.

That face when you realize someone is taking pictures of you.

#Finding 1: There are six native carnivore species and three non-native carnivore species in the region.

Our native carnivores from top to bottom:  fosa  ( Cryptoprocta ferox ),  spotted fanaloka  ( Fossa fossana ),  falanouc  ( Eupleres goudotii ),  ring-tailed vontsira  ( Galidia elegans ),  broad-striped vontsira  ( Galidictis fasciata ), and  brown-tailed vontsira  ( Salanoia concolor ).

Our native carnivores from top to bottom: fosa (Cryptoprocta ferox), spotted fanaloka (Fossa fossana), falanouc (Eupleres goudotii), ring-tailed vontsira (Galidia elegans), broad-striped vontsira (Galidictis fasciata), and brown-tailed vontsira (Salanoia concolor).

Based on old range maps, we expected four of the native carnivores to be present. Were we surprised when the brown-tailed and broad-striped vontsiras showed up!

Spotted fanaloka and fosa were the most common native carnivores and dogs were the most common non-native carnivore. The rarest native and non-native carnivore was the brown-tailed vontsira and the small Indian civet, respectively.

Our non-native carnivores from top to bottom:  dogs ,  feral cats , and  small Indian civets  ( Viverricula indica ).

Our non-native carnivores from top to bottom: dogsferal cats, and small Indian civets (Viverricula indica).

Fortunately, sometimes our camera traps were set to take videos instead of pictures. That’s how we got the first videos of wild fosa and ring-tailed vontsira in the region.

#Finding 2: Locals targeted non-degraded forests when hunting native carnivores.

A snare waits on a trail to trap any animal (carnivore or not) that walks through it.

A snare waits on a trail to trap any animal (carnivore or not) that walks through it.

The Malagasy people in the region hunt all sorts of species, from tenrecs to carnivores to lemurs [3]. We found that they targeted non-degraded forests for their hunting efforts, which makes sense. Why go grocery shopping in a picked-over gas station when you could go to a well-stocked Kroger?

Which were the species du jour? The most hunted species were the non-native small Indian civet and the native ring-tailed vontsira.


#Finding 3: Man’s best friend is no friend of Madagascar’s native carnivores.

Dogs were the equivalent of a rude roommate for four native carnivore species. You know the one. The one that plays loud music at random hours of the day, eats your food, and is constantly late with the rent. That one.Falanouc and broad-striped vontsiras avoided sites with dogs. Fosa became night owls where dogs where seen at high rates.

Unfortunately, Fosa is stuck with the lease. Falanouc and Broad-Striped Vontsira have already moved out.

Unfortunately, Fosa is stuck with the lease. Falanouc and Broad-Striped Vontsira have already moved out.

Brown-tailed vontsiras (which liked to be active at the same time as dogs) were also not found at the sites where dogs were present.


Native carnivores also avoided small Indian civets. Meanwhile, feral cats didn’t seem to make an impression.

What Does All This Mean?

Just like Madagascar’s first mongooses, our journey into the unknown ultimately came out all right. We found two carnivore species where we didn’t expect to. We learned that spotted fanaloka were not the delicate snowflakes that everyone was sure they were. We underscored the threat that local hunting can have on carnivores.

But questions remain!

Would we find different results if we moved our camera traps deeper into the forest, further from the forest edge and villages? Would more native carnivores be active during the day? Would we see higher numbers of the rarer little vontsiras?

What is up with the broad-striped vontsira? Despite 15 surveys at seven sites, we still know little about this cute critter with the skunk-inverse fur coat.

“You’re studying me? I’m gonna study you right back!”

“You’re studying me? I’m gonna study you right back!”

Why do fosa go into camps and eat soap? (Tastes good? ¯\_(ツ)_/¯)

We may learn the answers to these questions with more surveys, using different techniques (like GPS collars). Until then, Masoala-Makira’s carnivores will remain, for the most part, a mystery.


In ‘Makira Lessons’, a series in the making, I’ll sum up the main findings of my published Madagascar research — and any bonus unpublishable tidbits— in a way that is accessible to everyone. If you have any questions, feel free to hit me up on twitter or contact me.

The papers that inspired this post are:

Hunting, Exotic Carnivores, and Habitat Loss: Anthropogenic Effects on a Native Carnivore Community, Madagascar,

Patterns of Spatial Co-occurrence Among Native and Exotic Carnivores in North-eastern Madagascar, and

When Carnivores Roam: Temporal Patterns and Overlap Among Madagascar’s Native and Exotic Carnivores.

Literature cited:

[1] Ali, J. R., and Huber, M. 2010. Mammalian biodiversity on Madagascar controlled by ocean currentsNature 463: 653–657.

[2] Brooke, Z. M., Bielby, J., Nambiar, K., and Carbone, C. 2014. Correlates of research effort in carnivores: body size, range size and diet matterPLoS ONE9(4): e93195.

[3] Golden, C. D. 2009. Bushmeat hunting and use in the Makira Forest, north-eastern Madagascar: a conservation and livelihoods issueOryx 43: 386–392.