Viverrids: Long-tailed Palm Civets (and coffee...)

Common palm civet

While the palm civets do, arguably, form a single group of related animals, they are spread between two subfamilies that diverged at least 23 million years ago, at the dawn of the Miocene epoch. This is only about 5 million years after the split between the true civets and the genets, so it's fair to say that the two subfamilies are distinct. The subfamily that includes the animal originally known in the West as a "palm civet" is that of the paradoxurines.

The animal in question is now known simply as the common palm civet (Paradoxurus hermaphroditus). The alternative name of "Asian palm civet" is also often seen, although it has the disadvantage of not clearly distinguishing it from all the other palm civets that live in Asia. Which, since there are no palm civets outside of Asia, isn't really narrowing it down much.

The common palm civet is, however, undeniably common. It was first scientifically described all the way back in 1777 by Prussian naturalist Peter Simon Pallas, although it's not known where he obtained his specimen. It could have been many places, since the common palm civet is widespread and would have been known to many European colonists at the time. In fact, it's found across pretty much the whole of southern Asia east of Pakistan, occupying almost the whole of India and Nepal, plus Southeast Asia and southern China as far north as Hainan. It is also common on islands, including Sri Lanka, western Indonesia, and the Philippines. For that matter, they have been introduced to islands further east, notably Sulawesi, which somewhat muddies the picture.

Superficially, it resembles many other civet-like animals, being around the same size and shape. It has numerous spots across its body, which merge into three parallel lines running down its back. The face has black and white mask-like markings, the exact shape of which varies considerably between individuals. The scent glands are much less developed than they are in most other viverrid species, present, but without much in the way of detailed structure. Notably, the tail is unusually long, not much less than the entire rest of the head and body put together at 33 to 66 cm (13 to 26 inches). It often, but not always, has a white tip.

Palm civets are forest-dwelling animals, but as their wide range might indicate, they are tolerant of many different types of forest. They are found among palm trees at least half of the time, but that may be because such forests are particularly common in that part of the world. Otherwise, any sort of forest will do, and they seem surprisingly willing to put up with human disturbance. Under some conditions, they actually prefer it and inhabit plantations alongside secondary growth and deeper, more primeval jungles. 

A limiting factor may be the need for trees to sleep in during the day. They prefer those with dense foliage or creepers that can hide them, so while they may be common at night along roadsides, they also need denser woods nearby. On the other hand, many common palm civets sleep during the day in attics and similar human structures that offer good concealment. 

Compared with true civets, palm civets eat a lot of fruit, to the extent that this constitutes the great majority of their diet. They do eat insects and small mammals such as mice and wild gerbils, but less so than one might expect, with one study finding such remains in less than one in four of their scats, while fruit seeds were virtually universal. They may switch to animal prey primarily when fresh fruits are scarce, although this happens less frequently in the tropics than it would further north.

The fruit in question varies across their range. In India, for instance, papaya seems particularly common, and they will also drink the sap from tapped "toddy" trees on coconut plantations. Their preference for relatively large-seeded fruits may make them an important seed disperser, especially in disturbed habitats where other wild frugivores may be uncommon. For example, rambutan, a relative of the lychee, is often described as a fruit eaten by monkeys, but, in fact, macaques tend to spit the seeds out, while palm civets swallow them whole and deposit them hours later up to 270 metres (295 yards) away.

Another fruit commonly eaten, in places such as Nepal and Indonesia, is that of coffee plants. These are actually berries, similar in form to cherries, with the seeds being what we make the drink from. This, of course, leads to what may be one of the more popularly known facts about civets in general: the production of kopi luwak, or "civet coffee". This comes almost exclusively from the common palm civet (and not from any of the "true civets") and is produced from coffee beans that have passed through the animal's digestive tract.

While this is something they eat in the wild, they don't restrict themselves to the arabica beans that humans generally prefer, and it certainly isn't something they do in large volumes. As a result, most kopi luwak is produced on battery farms, where the palm civets are force-fed suitable beans and their dung collected. The digestive process affects the chemical composition of the beans, reducing some of the compounds that make them bitter, and increasing the proportion of fat, which likely gives a fuller flavour to the end product.

So it's true that the resulting coffee tastes different from the regular sort and, from most people's perspectives, probably better. It's just whether or not you want to drink coffee sifted from the dung of an animal that almost certainly won't have been kept in humane conditions.

Brown palm civet

Palm civets are solitary, with adults sleeping alone, and rarely using the same nesting site on consecutive nights. Even so, they aren't especially territorial, with multiple animals having been seen peacefully eating together at the same tree before going their separate ways. As with other viverrids, they communicate using the scent from their perineal glands, which allows them to distinguish sex and the specific identity of individuals they are familiar with. Mating takes place throughout the year, with the female giving birth to a litter of up to five young two months later. Like those of cats, the newborn young are blind and helpless.

It has been suggested, on the basis of mitochondrial DNA, that the common palm civet represents three species: one on the mainland, one in peninsular Malaysia, Sumatra, and Java, and the other further east in Borneo and the Philippines. This does not seem to have been widely accepted yet, but it is becoming more popular, so that may well change soon. Two other species, however, have long been regarded as separate.

The brown palm civet (Paradoxurus jerdoni) is distinguished by its relatively uniform brown colour. It lives in the Western Ghats, a mountain range along the southwest coast of India, where it is found from almost the southern tip of India in Kerala to at least as far as Goa, and likely a little way beyond. It lives in rugged and mountainous woodlands, not venturing below 280 metres (900 feet) elevation. 

One study found that they prefer to sleep through the day in fruit trees, notably mango and roseapple, often using abandoned squirrel nests to make themselves comfortable. About 90% of their diet consists of fruit, most commonly small berries, although they also eat some larger fruits such as Ceylon olives (which are unrelated to actual olives). Although they do occasionally enter plantations, they do not do so as frequently as the common palm civet, and their rugged homeland, while not immune to human encroachment, is perhaps less so than the lowlands. It also seems relatively numerous across a mountain range that's rather longer than many in the West may realise, and so isn't considered a threatened species.

Golden palm civet

We know even less about the golden palm civet (Paradoxurus zeylonensis) beyond the fact that it is golden to ruddy in colour, and lives in inland areas of Sri Lanka. They seem to be willing to use a range of different forest types, from sea level to low mountains and, like the common palm civet, tolerate those that have been altered by human activity. They are less likely to be seen near human settlements, but that may just be because the more numerous common palm civets keep them out. They may, however, be better at climbing, having been seen moving along telephone wires.

The masked palm civet (Paguma larvata) is much better known. It is another widespread species, being found across southern and central China, much of Southeast Asia, along the foothills of the Himalayas as far west as Pakistan, and on Borneo, Sumatra, and Taiwan. However, it is not in these areas that it has been most thoroughly studied, but rather in Japan, where it is not native. It has lived in the country since at least the late 19th century, with genetic analysis showing that the animals arrived there from Taiwan, but are sufficiently varied that they must have been introduced to the islands multiple times.

The masked palm civet is slightly larger than its relatives, weighing in at 4 to 5 kg (9 to 11 lbs) and has a grey, unspotted body. What makes it distinctive is the mask, which is more prominent than on the common palm civet, with a white stripe down the centre of the face, black patches to either side, and smaller white spots under the ears and eyes. The tail, while long, is not quite so much, in proportion to the body, as in the Paradoxurus species.

It mostly inhabits warm evergreen forests, but also utilises deciduous forests in some parts of its range, especially in the Himalayan foothills. While it is found at a range of altitudes, in Indonesia it is more common on mountain slopes than in the lowlands; this may, of course, be a reflection of where humans are least likely to be rather than a genuine preference.

Masked palm civet

It is thought to be more omnivorous than its close relatives, with perhaps a third of its diet consisting of rodents and other small animals. In the more northerly parts of its range, where the climate is more temperate, it switches from fruit in the summer and autumn to animal prey in the winter and spring when the former is less available. 

Like the others, however, it is a solitary and nocturnal animal. In southern China, individuals have been reported to occupy home ranges of about 190 hectares (470 acres) each, and it's similar even in the much richer jungles of Borneo. It's likely that this degree of travel means that the masked palm civet, like the common one, is a seed disperser, if perhaps not quite of the same level of importance. They are less active in winter, probably conserving their energy in a time of food shortage.

Interestingly, while adults stay apart, juveniles learning to forage for themselves may not only rely on their mothers to help them out, but may seek out help from other adult females (possibly their aunts), grooming them in return for support in a way that is more typically seen in group-living animals. The manner of their mating has also been described as unusual, consisting of repeated sessions of prolonged thrusting intercourse with only a single ejaculation.

Masked palm civets are significant in a less positive way, as well, in that they were probably the source of the SARS epidemic in humans, which jumped species in a market in China in a similar way to the currently most favoured theory of the origin of the later Covid pandemic. This may have been rendered more likely by the fact that genetic evidence shows wild individuals are often introduced to civet farms, potentially bringing in viruses from outside.

This brings me almost to the end of the list of recognised palm civets. However, there are two other species in the same subfamily as those listed above, one of which is sufficiently odd that it isn't called a palm civet at all. Next time, I will conclude my survey of the viverrids by looking at these two...

[Photos by Mike Prince, David V Raju, Mahendra Prasad Peiris, and Rejoice Gassah, from Wikimedia Commons. Cladogram adapted from Nyakatura et al 2012.]