Sunday 28 October 2012

Weasels of Mystery: the Ferret-Badgers

Chinese ferret-badger
So far, in my survey of the weasel family, I have covered a number of familiar species: stoats, badgers, and otters, among many others. There have also been a few species probably less familiar to those of us in the west, such as zorillas, grisons, and tayras. But the least studied of all belong to the last subfamily I have to cover: the ferret-badgers.

Ferret-badgers are, of course, neither ferrets nor badgers, but entirely their own group. As the English name implies, they have features some way between the two animals for which they are named, although they are distinct in a number of ways, too. Their total body length is not far off that of a ferret, but they have the stocky build of a badger, and so somewhat resemble a smaller, slimmer, version of that animal. Proportionally, though, their tail is longer than that of a badger, and they have a narrower, more pointed snout. They have greyish or brownish fur over most of the body, which, again, looks quite badger-like, and black-and-white markings on the face.

However, these markings are not the clear stripes of a badger, although they aren't really the 'mask' pattern found on ferrets, either. One distinctive feature of the markings is a white stripe running from the forehead down over at least the neck, and often further down the middle of the back. American badgers have something similar, but it's often more striking in the ferret-badgers. Like many other members of the weasel family, the creatures are said to have a strong odour, and they're also quite fierce, so it could be that the highly visible markings serve as a warning to other animals.

Ferret-badgers live in eastern Asia, and their native habitat seems to be a mix of forest, open woodland, and pasture. They are not particularly worried by the presence of humans, and can often also be found in agricultural land. Despite this, their relationship with humans is somewhat ambiguous. Apparently, some locals allow them into homes in order to catch vermin, but at the same time, the animals are hunted for fur and meat. They also, like many small fierce animals, can carry rabies.

The reason that they have a badger-like build is that they, too, are good at digging. They're nocturnal, and often live in burrows, but they're just as likely to rest during the day in natural hollows of any kind, and they don't necessarily use the same one from day to day. Being smaller than badgers, they are also able to use their strong digging claws to climb up trees, although they don't choose to do so very often.

Like many other members of the family, they eat whatever small animal they come across, including rodents, insects, and so on. They can also use their claws to dig up things like earthworms. However, they are omnivorous, and a significant proportion of their diet consists of fruit of various kinds. It has been suggested that they may play a role in dispersing seeds, although they don't seem to be very good at it - the seeds pass through the gut largely unaffected, but the ferret-badgers prefer to leave their droppings in places that aren't suitable for them to germinate. Which, from the plant's perspective, rather defeats the point.

Although they are generally solitary, they are less anti-social than many other mustelids, and several animals may live in the same area, with greatly overlapping territories. Presumably, therefore, they must regularly come into contact with one another without resorting to violence. They breed in the spring, giving birth around May or June to a small litter of three or four young. The young are born blind, but fully furred, and may stay with their mother for an unusually long time: in one instance, a mother was reported to still be suckling a pair of young when they were nearly fully grown. They have lived for up to seventeen years in captivity, which isn't bad for an animal of their size.

You might think, given how much I've been able to say about them above, that they can't be that badly studied. There's some truth in that, but the thing is that everything I've just said refers to just one species: the Chinese ferret-badger (Melogale moschata), often also called the "small-toothed ferret-badger". This is found throughout southern and central China, parts of north-eastern India, and into Laos, Myanmar, and Vietnam, as well as on the island of Taiwan. Research into the habits and ecology of this animal are, on the whole, preliminary, but at least they exist, and enable us to build up the picture I have just described.

We can say rather less about the other species.

There are, in fact, at least four other species of ferret-badger besides the Chinese one. They all look remarkably similar, with little more than subtle distinctions of their coat pattern to tell them apart. Given that the appearance of individuals within each species is rather variable, this makes the different kinds very difficult to tell apart, without using blood tests or (more realistically) judging by where in the world they happen to live. Because they are so similar in appearance and build, it's probably fair to say that they are similar in their habits, as well - but information to confirm this is sparse at best.

Of the three, the least mysterious is probably the Burmese ferret-badger (Melogale personata). It's slightly more heavily built than the Chinese species, and with a longer tail. As its alternative name of "large-toothed ferret-badger" suggests, it also has larger teeth than its cousin. The stripe down the back tends to be longer, too, sometimes reaching the base of the tail, but this isn't a very reliable guide to telling them apart.

It lives broadly further south than the Chinese species, in Myanmar, Vietnam, Laos, Cambodia, Thailand, and Nepal. However, there is a considerable range, from southern China to north-eastern India and northern Indochina, where both species are found side by side. The difficulty of telling them apart makes conservation studies difficult, and while its probably not in any great danger as a species (the Chinese one isn't), we don't have enough information to know for sure. What little we do know confirms the guess that it is very similar in habits and biology to the Chinese ferret-badger. For instance, we know that it's nocturnal, often lives in burrows, eats much the same food, and has a similar breeding pattern.

Javan ferret-badger
The Bornean ferret-badger (Melogale everetti), is found only on the northernmost parts of that island, while the Javan ferret-badger (Melogale orientalis) is found only in small areas in the east and west of Java, and also on Bali. We know next to nothing about these two species, and their physical appearance is quite remarkably like their kin. Given where they live, it's plausible that the Javan species in particular is threatened by loss of habitat, but realistically, we don't know enough to say for certain.

The jungles of south-east Asia are just about the best place in the world one can think of to hide an unknown species of land-dwelling animal. While the Chinese ferret-badger, in particular, may actually represent more than one species, just last year there was an announcement of a new species that was previously entirely unknown. For lack of any official alternative that I know of, I am going to call this animal (Melogale cucphuongensis), the Vietnamese ferret-badger. It's known from only two specimens, one of which wasn't preserved, and its probable that the only reason it was spotted in the first place is that, unusually, it looks quite different from any other ferret-badger.

It has the same shape, size, and so on, so there's no doubt that that's what it is, but it has a much darker, more uniform colour. Unlike all other ferret-badgers, the face is brown, with only a few white spots, and a very narrow stripe on the neck. In other words, there is no trace of the black-and-white markings that give ferret-badgers their distinctive appearance. Genetic analysis confirms its distinct status - that is, it's not just some weirdly coloured individual - and that it may have diverged from the other ferret-badgers before the Chinese and Burmese species parted company.

How it relates to the two island species, or how they relate to each other, is anyone's guess. That's why there's no cladogram this week: the studies necessary to construct one simply don't exist.

[Painting by Joseph Wolf (copyright expired), photo by Kisp√°l Attila from Wikimedia Commons]

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