Viverrids: Civets Great and Small

Small Indian civet

Most species of true civet weigh somewhere between 7 and 9 kg (16 to 20 lbs), somewhat larger than a domestic cat, and similar to a King Charles spaniel or a Highland terrier - albeit of a more slender shape. The large Indian civet (Viverra zibetha) is at the upper end of this range, the second-largest species of true civet. The name of the large Indian civet, however, tends to imply that there must also be a smaller version in the same general area, and so there is.

The small Indian civet (Viverricula indica) is the smallest of the true civets, between 48 and 68 cm (19 to 27 inches) long, not including the tail, and weighing just 2 to 4 kg (4½ to 9 lbs) - more of a toy poodle or a Pomeranian in terms of dog weight. Otherwise, it looks much like its larger cousin, although it has block spots like a Malay civet, rather than the fainter blotches of its larger namesake, and does not have the crest of erectile hair running down its back. The smaller size caused it to be placed in a separate genus from the other civets as early as 1838, and modern genetic analysis has shown that this is fair; the two parted company about 12 million years ago, while the other Asian civets are much more recent than that.

The small Indian civet is both common and widespread, being found across the whole of southern Asia from eastern Pakistan to Shanghai and Taiwan, and reaching Sri Lanka and Singapore in the south and perhaps more surprisingly, Java and Bali. At least twelve subspecies have been proposed to exist across this range, but a genetic study in 2017 was able to confirm only four of them. This included both the Javanese and Balinese populations, but the researchers weren't able to collect samples from mainland China, among a few other places, so the true story may be more complicated.

The animal has also been introduced to other Indonesian islands, and to places as far away as Madagascar. This is, as so often with civets, because of the chemicals in its perineal scent glands, which can be used for making perfume. The glands are well-developed, with distinct lips that are poked out when it sprays - targeting, as cats do, almost any vertical object. They are present in both sexes, but larger in the males.

They are woodland animals, preferring dry forests to humid jungles. They may be found on the fringes of rainforests, but do not venture far inside. Other common habitats include scrubland, bamboo stands, and wooded riverbanks where the vegetation is not too dense. Studies in Shanghai indicate that some will enter urban environments, making use of parks and other patches of greenery, but that they restrict their activities to the hours around midnight, when humans (and also stray cats) are least likely to be around. Elsewhere, while they are always nocturnal, their activity is more spread out through the night, peaking in late evening and early morning when there is more light to see by.

This also happens to be when many local rodents are most active, and one can see the advantages of that to a small omnivore. In fact, rodents are perhaps their most common prey, with their remains being found in 90% of their scats according to some studies. Insects and worms are also a significant part of their diet, and, while they seem to prefer animal food, they do eat leaves and fruits. On the other hand, birds, fish, and snails are only a minor component of their food, something eaten when the opportunity presents itself but not actively sought out. They also seem to ignore rice, even when they hunt in paddies, which must be a help to the local farmers.

They are solitary, with males in particular marking their territory with their spray. Individuals have been reported to have home ranges of between 2 and 3 km² (500 to 750 acres). Although they can climb trees if they have to, they sleep during the day under dense shrubs or, if they get lucky at finding a pre-made one, in holes in the ground. They are not especially vocal animals, although they do make alarm calls when stressed and females have been recorded screaming at males in captivity when the latter get aggressive.

The only other call they are known to make is a "da-da-da" sound used by males to entice females in heat. This happens in the spring, and occasionally also in autumn, lasting 12 to 15 days. Males scent mark just about everywhere when they are aware of a nearby receptive female, although the latter only do so in their immediate vicinity, probably hoping the male comes to them. Courtship is aggressive, with the female initially fighting and screaming before she calms down and encourages the male to mate. In one study, she gave a call when she had had enough, which the male respected, but then got bitten for his trouble anyway. 

Pregnancy lasts about 67 days, during which time, and for two months after giving birth, the female stops scent marking altogether, probably wary of giving away her position while vulnerable. She gives birth to a litter of two to five furred, but blind kittens, whose eyes open after five days.

African civet

At the opposite end of the scale, the largest of the true civets is the African civet (Civettictis civetta). Ranging from 67 to 84 cm (26 to 33 inches) in length, not counting the tail, they typically weigh between 10 and 15 kg (22 to 33 lbs), although larger individuals have been recorded. They have a similar spotted pattern to some Asian civets, but the background coat is brown or reddish, rather than grey, and the erectile crest down the back is more prominent. Despite living on a different continent, they are more closely related to most Asian civets than the small Indian species is.

They are also perhaps the most widespread of the civet species, being found across the whole of Africa south of the Sahara and north of the southern arid belt; Lesotho is the only sub-Saharan African nation they are not recorded in at all, although they inhabit only the more northerly parts of Nambia, Botswana, and South Africa. Within this broad region, they inhabit a wide range of woodland and savannah habitats, avoiding only the densest jungles, unless rivers or logging roads make access easier.

African civets are highly omnivorous, with analysis of their diets in different areas, or even in the same area at different times of the year, showing it varying from 65% plant-based to 65% animal-based. They also do not seem to discriminate much, eating a wide range of fruits, leaves, and roots alongside rodents, birds, insects, and millipedes. Indeed, they eat enough fruit that they are important distributors of seeds, with clumps of seedlings germinating in hollows they have rested and defecated in and at their shared latrine sites. 

The home range of African civets has been reported to be relatively small, around 0.8 km² (200 acres), perhaps because they live in fertile areas where they do not need to travel far to find food. They scent mark their latrine sites, which are situated along trails close to their resting sites, as well as prominent vertical objects such as tree trunks. The perineal scent gland is, like that of other civets, well-developed, formed of muscular, paired hair-lined sacs and distinct lips. Anything up to 2g (~ 1/8 of a tablespoon) of civet oil may be deposited on each visit, although, in practical terms, collecting this from civet latrines in the wild as an alternative to farming the animals yields no more than half this. Males have larger glands than females and produce a stronger-smelling scent. 

African civets also possess small anal scent glands, marking their dung directly, rather than via spraying. The purpose of these remains unclear, although it seems likely that they must provide some additional information to the species that the main glands cannot.

There is no distinct mating season, with mothers able to give birth to two to three litters each year. Mating seems less aggressive than in the small Indian civet, although the female snaps angrily at the male at the beginning of courtship, before eventually inviting him to chase her as an immediate prelude to the act. Litters of up to four are born after a 73-day pregnancy, and, from the limited observations conducted, apparently with their eyes open. They can stand on all fours at five days, which is also quicker than is the case with many other carnivores.

The African civet is the only true civet living in Africa today, although at least one close fossil relative is known to have lived there in the last few million years (that is, since Africa and Asia shared a land bridge). It is, however, far from the only viverrid on the continent, and next time I will be looking at some of the others.

[Photos by "Tomio 34456" and Nikolai Usik, from Wikimedia Commons. Cladogram adapted from Gaubert et al. 2006.]