Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours ... but actually many media including 'digital' paintings with the computer!"

When people think of threatened species, they often think of large and fairly spectacular things like whales, tigers, rhinos, or pandas. It is true that most or perhaps *all* large mammal species, apart from us (we are quite large mammals too, after all) are threatened – we're pushing everything else out, as our population keeps growing. But there are also many smaller mammals that are threatened as well. One such species is the Riverine Rabbit of South Africa, scientific name Bunolagus monticularis.

Though it is called a rabbit, in some ways it is more like a hare. For those who don't know – the primary differences between rabbits and hares in Britain and Europe, are:

1) Hares are longer and lankier in body shape than rabbits, with longer ears. While rabbits dive into shelter when threatened, hares will usually try to run away.

2) Hares give birth in an open hollow called a ‘form', to open-eyed, active babies (they're called leverets). Rabbits give birth in burrows, to young (called kittens) that are blind and helpless, needing a few days before they become active.

This scheme works for rabbits and hares in Europe, where only a couple of species of lagomorphs (the group to which Rabbits and Hares belong) occur, and those species clearly fall in one or the other category. In the rest of the world, however, there are lagomorphs that aren't quite as clearly rabbits or hares. The Riverine Rabbit is one of these. Unlike a rabbit, it has long ears, and unlike a hare, it gives birth to helpless kittens in an underground burrow dug by the female. In body build it is not lanky like hares, having fairly short rear legs, and when fleeing it has a rather scurrying gait.

The Riverine Rabbit, thus not quite being a rabbit or a hare, might in its genes carry a lot of information about the early evolution of rabbits as well as hares. This makes the Riverine Rabbit very important for understanding biodiversity. There are a few other such rabbits/hares in the world – that have apparently branched off the family tree before ‘real' rabbits and hares have evolved – but they, too, are all rare and/or threatened.

Species like these are called ‘relic species'. In a sense, they are evolutionary holdovers, representatives of kinds of things that were abundant and widespread long ago, but that became displaced almost everywhere by newer evolutionary developments … more ‘modern' or ‘highly evolved' species. Nevertheless, these ‘relic species' have managed to hold on in a few places where for some reason they have an advantage, or the more common and ‘modern' species have a disadvantage. It would be wrong to call them primitive or poorly adapted, though. For after all, they are still here … they are every bit as modern as the present day. It is only a very, very new factor – namely, US HUMANS – that have in recent years pushed many of these relic species to the brink. If we push them over the brink, then and only then can we say they have lost the battle … but, how about, instead of helping them off this planet, we do what we can to help them to stay around?

Outwardly, the Riverine Rabbit is quite pretty. It has a reddish brown coat with grey grizzling on the back, while its underparts are creamy yellow. Its eyes are outlined in white, and there are white lines along the front edges of its ears as well. Most characteristically, it has a prominent black stripe along each cheek, separating a creamy white chin and cheeks from the brown of the rest of the face. In this, the Riverine Rabbit is one of the most distinctively marked of all rabbits or hares. It is only trumped by the two species of Striped Rabbit of the genus Nesolagus(both extremely rare and threatened):

Riverine Rabbits are fairly small, weighing in at 1.4-1.9 kg (3 to a bit over 4 lbs). Females are actually a bit heavier than males.

These little rabbits are nocturnal. They come out at night to feed on grass – when it's available (only after good rains) – or the aromatic foliage of Buchu, Salt Bush or Ink Bush shrubs. During the day, they rest in forms (scraped-out hollows) under bushes.

The problem with this rabbit is its very localized distribution. It only occurs in the valleys of a number of rivers in the Karoo region of South Africa. Since the Karoo region is quite dry, there are not many rivers, and those that exist only flow rarely. But when they do, they sometimes overflow their banks along broad alluvial plains. They then deposit very fertile silt along their banks – this fertile soil being sought after by farmers. Once again, in the dry Karoo these are the only really suitable areas for raising crops.

So, there was an attempt to turn these fertile river valleys into farmland. About 60% of this habitat has been destroyed – ploughed over and planted with wheat. This project has actually failed: the region is just too dry; it won't work without irrigation, and in this forbidding region that is not practical. So, the habitat has been destroyed for nothing. It will take very long for the natural vegetation to re-establish itself.

The rabbits of course can't easily find new homes. They are dependent on the dense shrubs that grow along the rivers – on the open plains they will be too exposed, and the soil is too rocky for them to dig their burrows in. They can only live along those narrow, sandy, densely vegetated strips – only one or two hundred yards wide – that fringe the rivers.

Even in areas where the river valleys haven't yet been turned into farmland, the rabbits suffer from other threats. People still cut down bushes and trees along the rivers for firewood, and many areas are overgrazed by sheep. Rabbits are sometimes hunted by men with dogs – or caught by stray dogs. They are also caught in traps set for small game. Also, some of the rivers have been dammed upstream, causing reduced flow of water in the lower reaches, leading to die-off of the riverine vegetation.

A final problem with Riverine Rabbits is that they do *not* breed like rabbits! In fact, a doe usually only produces 1 or 2 young a year. This is a typical situation of a species with limited available habitat. Many species of mammals or birds that live on islands are the same … they have only a few young and breed only infrequently. This is because they would otherwise overpopulate their available habitat. But of course when new, predacious things like humans enter their habitat, this makes them extremely vulnerable.

All in all, these problems have caused a serious decline in the Riverine Rabbit's numbers. It probably never was very abundant in recent times – though, in the distant past, it certainly was much more widely distributed, and much more numerous. Estimates suggest that originally its habitat could have supported about 1 500 individuals, but now its population has shrunk to perhaps only 200 or so animals in the wild, in total. This makes it one of the 50 rarest mammal species in the world (that we know of).

Fortunately, there have been projects over the past decade or two to inform farmers of this unique mammal, and several farms have been declared ‘conservancies', with the farmers pledging to destroy no more riverside vegetation, and also to do what they can to minimize other threats like overgrazing or hunting. Some rabbits have been bred in the De Wildt Cheetah Research Station and subsequently introduced into the Karoo National Park. Thus, there is hope for this pretty and unique little mammal's continued existence.

Willem

28.02.11 Front Page

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