Colours of Wildlife: Cape Porcupine
Created | Updated Jul 20, 2014
Cape Porcupine
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!"
This is the Cape Porcupine, Hystrix africaeaustralis. It is a big, stocky, powerful rodent, indeed the largest rodent in Africa. Adult porcupines can reach 30 kg/66 lbs in weight. They look bigger than they are, since they are covered in long spines and bristly hairs. The name 'porcupine' comes from Middle French 'porc espin' which means 'spiny pig'. They have rather pig-like snouts, but are no close relations, rodents being very distantly related to artiodactyls! The scientific name comes from the Greek name for porcupine, 'hystrix', and 'africaeaustralis' which simply means 'South Africa'. Although characteristic of the southern part of Africa, the species occurs as far north as southern Kenya and Uganda. Further north than this it is replaced by the very similar Crested Porcupine, Hystrix cristatus. In Afrikaans we call a porcupine an 'ystervark', or 'iron pig'.
Though I've been living around porcupines all my life, I've only seen them on a handful of occasions. They are nocturnal, spending their days in burrows or other shelters like small caves or crevices in rocky places, cavities below tree roots, or the holes dug by Aardvarks. Only when night falls are they out and about. But they leave evidence of their activities all around! Since I was a small child, I've enjoyed picking up porcupine quills I found in the veld. They shed these easily, and the quills are commonly used for decorative purposes over here. Also, porcupines are powerful diggers and their holes and scratchings are very conspicuous. I've once had a porcupine in my garden! It did a good deal of damage to some of my plants, but then left and we repaired the holes under the fence where it got in and it hasn't been back since.
The Spines of Porcupines
This porcupine and other old-world porcupines have quills that are rather different from the quills of the new-world porcupines. Those mostly have short spines that are hidden in their long, bristly fur and soft underfur. Their spines have barbs, which mean once they're embedded in your flesh, they're very hard to extricate!
The Cape porcupine's spines are not barbed like that, but are very long and sharp. They are also visually impressive, being banded in black and white. Quills are indeed hairs, but heavily modified. They are very long, thick and hard, with a very tough outer layer of keratin, and a pulpy or hollow centre. The quills are loosely embedded in the porcupine's skin, and clustered around the rear half of the body. When a porcupine feels threatened by a predator – or any animal – it raises its quills. Along with the very long crest of bristly hairs on the porcupine's head and shoulders, these make the porcupine look very big and threatening. The bristles reach a length of 50 cm/20", and the quills can reach 30 cm/12". The porcupine also has special short quills in its tail, that are hollow and attached by thin stalks. Wiggling its tail causes these quills to rattle. It will also growl and stamp with its feet. So, stamping, growling, bristling and rattling, the porcupine will try and intimidate and dissuade anything from trying to eat it!
Should the threat persist, the porcupine will go into action. It will turn itself so the quills are towards its attacker, and will charge towards it – backwards or sideways as the case may be. If the assailant doesn't get out of the way fast enough, it will find itself with a new set of piercings and flamboyant embeds! Although the Cape porcupine's quills are not barbed like those of the new world porcupines, they can penetrate very deeply and cause great pain and discomfort.
These spines also protect porcupines while they're in their burrows or shelters. They enter head first, so that their quills will point backward to the burrow's entrance. They will expand the spines to fill all of the entrance, forming a spiny barrier for anything else trying to get in. The spines also 'wedge' the porcupines in against the burrow walls, making them very difficult to pull out.
Porcupine Myths
There are some myths attached to porcupines and their spines, and I can remember when I was a kid, having to bust some of these myths expressed by other kids. I don't know about kids today, if they still believe these myths … I actually worry that they might have no ideas about porcupines at all! But to get to the myths, the first is that porcupines can actually shoot their spines at their attackers. This is not true. Although porcupines can control their spines with muscles, this goes only to the point of raising or lowering them, or rattling the ones in their tails. There is no mechanism by which the spines can be detached and propelled outward. It is only because they are loosely embedded in the porcupine's own skin that they detach and are pulled out when they stick in something else.
The other myth about porcupine quills is that if they stick in something's flesh, even if they don't go in deeply at first, they will 'work their way' forward over time until they eventually puncture a major organ. So the belief is that a single porcupine quill can in this way eventually kill even a big mammal like a lion. This is not true either. Porcupine quills that go in deep might get shoved in deeper still by an animal's activities, bumping against things, but they might equally likely fall out as well. They still can kill a large animal like a lion, but only if the wounds they inflict become septic, or if spines around the mouth cause so much pain that the lion can't eat properly any more.
Eating Porcupines
Still, it might surprise you how many predators will in fact catch and eat porcupines. Lions do so, and regularly. In the Kalahari Desert, porcupines are a major food item for the local lions. Leopards will try their luck with them too. They are cats after all, and cats are very deft and coordinated. The trick to catching and killing a porcupine is to knock it over and to go for the unprotected underparts. Large eagles can do this too. But despite all their deftness, lions and leopards frequently get quilled. They do not have opposable thumbs and dextrous fingers to pull these out of themselves, so they will have to wait until they fall out. Only a small percentage of lions or leopards so afflicted will suffer serious harm from these injuries.
Incredibly, lions sometimes ingest large numbers of porcupine quills when eating them … and pass these quills in their droppings!
Porcupines Eating
Now you know what eats porcupines, but what do porcupines eat? They're vegetarians, like most rodents, with very long, strong front teeth for gnawing. They eat noisily, the crunching being audible from some distance. They use their stubby but strong front feet with long claws for digging out roots, bulbs and tubers. They also eat fallen fruit. My illustration shows one eating Gemsbok Cucumbers, Acanthosicyos naudinianus, a valuable source of nutrition in the Kalahari Desert. Porcupines can be a serious problem around human gardens or farm fields. They also eat the bark of trees, sometimes ring-barking large individuals. They are generally rather destructive feeders, damaging more than they ingest.
You might actually get the idea that they are far more dangerous than they even seem. Suppose you find a den clearly used by a porcupine judging by all the spines left around it. You inspect it … there's more than just spines left there! There are bones … white bones of a large array of different critters! Is the porcupine indeed more than a peaceful vegetarian? Is it something more like the Killer Rabbit of Caerbannog?
Actually what happens here is that porcupines do indeed collect bones, but only of deceased animals – they do not kill these themselves. They carry the bones to their dens where they gnaw on them. They might do this to wear their teeth down and keep them sharp … like all rodents their font teeth grow throughout their lives and have to be constantly used to make sure they don't grow too long. But chewing on the bones may also provide the porcupine with needed minerals like phosphorus. Porcupine teeth are incredibly strong; they can gnaw on ivory tusks, can chew through trees 15 cm/6" in thickness and even through steel wire and bars.
Very Carefully
This is of course the answer to the question, 'how do porcupines mate?' These are among the animals in the world for which penetrative rape is impossible; the female absolutely has to cooperate for mating to happen (this is true for hyenas as well). Not only must the female lift her tail high over her back to allow the male to approach her from behind, she also only is in oestrus for about nine days per year, her vagina being closed by a membrane for the rest of the time. The female will initiate mating. She will present herself to the male and show him that she's ready by moving close to him and lifting her tail. He will rear up and mate with her. He finishes quickly, but afterwards he and she will spend a bit of time together grooming each other.
At the end of mating the male deposits a substance that hardens to form a plug in the female's vagina, meaning she can't be inseminated again … at least, for two days, after which it dissolves. But this helps assure that the babies born are really his. The gestation period is about three months, and she bears a litter of up to three babies. You will be relieved to know that at birth their quills are very soft. They are born in a special chamber in the den, lined with soft grass. Unlike many other rodents, baby porcupines are born with open eyes and are able to move around on their own. Their spines harden rapidly. Their mother suckles them for about six or seven weeks, from nipples at the side of her torso just behind the shoulders. The babies communicate by squealing. They accompany their mother for up to a year. Porcupines in nature live for about ten years, in captivity for up to twenty years.
Porcupines of the World
Porcupines fall into two groups: New World and Old World procupines. Actually these two groups are not very closely related, being classified into two separate families. The New World porcupines are able to climb trees, generally smaller, and as I've said have shorter spines with barbs. They are indeed closer relatives to other new-world rodents like capybaras, Guinea pigs and chinchillas, than to old-world porcupines. The old world porcupines, found in Africa and Asia, are terrestrial, good diggers, and with longer, more bristly spines. Some like the brush-tailed porcupines are not very spiny, and rather rat-like. Other African porcupine relatives include cane rats, Dassie Rats, and mole rats.