Old World Porcupines: Hystricidae

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OLD WORLD PORCUPINES: Hystricidae

INDIAN CRESTED PORCUPINE (Hystrix indica): SPECIES ACCOUNTS
SOUTH AFRICAN PORCUPINE (Hystrix africaeaustralis): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

The Old World (living in Africa, Asia, and Europe) porcupines (called "quill pigs" in Latin) take their English name from the formidable spines, quills, and bristles that cover their sides, back, and tail. Their heads and bodies together range in length from between 13.8 to 36.6 inches (35 to 93 centimeters) and the animals usually weigh between 3.3 to 66.1 pounds (1.5 to 30 kilograms). The eleven species fall into three genera ( JEN-uh-ruh; plural of genus): Hystrix, the Old World porcupines; Trichys, which are more slender mammals with flatter, shorter, and less-developed quills; and Atherura, which includes the brush-tailed porcupines. Most of the species have short tails, but others can have tails up to half of their head-body length. Eyes are usually small and can see only poorly, but the mammals' small ears are very keen. Nostrils are often S-shaped and contribute to a strong sense of smell.

Species in the Hystrix genus ( JEE-nus) are stocky, somewhat lumbering animals with rounded, blunt heads; mobile, fleshy noses; split upper lips; and coats of thick flattened or cylindrical spines. The mammals stay on the ground at all times, never venturing into trees like their cousins, the New Age porcupines of North America. Hystrix alone among the porcupines has chambers in its skull that can be inflated, possibly to increase the ability to smell underground food sources. This slow-moving genus has short, thick front and back feet, with five digits on each foot, although the "thumb" on the front feet is much smaller than the other digits. Their claws are short and the pads on their feet are bare and smooth. The whole sole of the foot touches the ground when the animals run or swim. These porcupines have black or brown white-banded, barbless (no barb, or hook on the end) quills that can reach up to 7.9 inches (20 centimeters) in length. The longest spines are usually on the hindquarters and the shortest on the cheeks. Their short tail is tipped with many thin, open-ended quills that rattle loudly whenever the animal moves. If some quills detach during a fight, the area will grow back new ones.

In animals of the genus Trichys, spines are short, relatively flat, and not well developed. These more slender species, which look almost more like bristly weasels than porcupines, do not rattle their spines when they move or when threatened. The species of the genus Atherura are rat-like creatures with unusually long tails tipped with a tuft of bristles. The tail is easily broken. Their spines are also flattened, but stiletto-sharp quills on their backs and sides make them intimidating opponents. Webbed feet make them good swimmers, and they readily climb trees as well. All of the Hystricidae species are primarily nocturnal, hiding from predators during the day. Except for the genus Trichys, spines normally lie flat when the animals are relaxed, but can be raised instantly into a bristling, quivering mass when threatened. All of the Old World porcupines have large, chisel-shaped upper and lower cutting teeth (incisors) that grow continuously throughout their lives. They are reputed to be quite intelligent animals, as evidenced by their uncanny ability to avoid traps. They normally live about ten years in the wild, and average twenty years in captivity, which they seem to tolerate well.

GEOGRAPHIC RANGE

Old World porcupines tend to live in the warmer habitats of southern Europe, many islands of the East Indies, across southern Asia (particularly India and the Malay Archipelago), and through all of Africa.

HABITAT

Old World porcupines generally like to live in deep burrows, which they often dig themselves or appropriate after the former occupants leave. However, they will also live in caves, rotting logs, nooks in rock walls, and hollow trees.

DIET

Mostly herbivores, plant eaters, Old World porcupines eat numerous kinds of plant material and human-cultivated crops. Some of their favorite foods are sweet potatoes, onions, bananas, grapes, corn, pineapple, cucumbers, and mangoes. They sometimes eat rotten meat (carrion) and chew up the bones as well, probably for calcium. They also chew on bark, branches, and tree trunks to keep their incisor teeth worn down to acceptable levels.

BEHAVIOR AND REPRODUCTION

Legendary for their ability to defend themselves, Old World porcupines (like their New World relatives) use their formidable spiny armor to fend off predators (mainly birds of prey, hyenas, pythons, large owls, leopards, and wild cats). Except for Trichys species, these shy, rather anxious creatures generally try to scare away an opponent first by clicking their teeth together, grunting and huffing, and stamping their hind feet, which rattles their quills to make an intimidating buzzing noise. If that tactic fails, the porcupines launch a lightning-fast backward or sideways charge toward the predator in an effort to puncture the offender's skin deeply with its quills.

The mating habits of porcupines are the subject of many jokes and much curiosity. The truth is close to the old punchline, "Very carefully." Old World porcupines engage in a complex courtship that occurs once (occasionally twice) a year from March to December. It involves a mating dance during which the male showers the female with urine. If she rejects her suitor, the female becomes very aggressive, stamping her feet and shaking her quills. If she approves of the male, he will stand still in front of her and then move toward and away from her many times while making certain sounds. The final phase of the courtship occurs when the female raises her hindquarters into the air and lowers her chest to the ground. The male approaches and mounts her with one paw on each of her sides, holding on loosely but not leaning on her at all. Their intercourse is accompanied by loud squeals, grunts, and whines.

A MYTH DISPELLED

It is not true that porcupines can "throw" or project their quills in any way, but they do detach easily—sometimes just when the animals rattle them to try to scare away predators. The quills do not carry poison, although bacteria on the shafts often cause serious infections if they puncture deeply enough. Infections eventually kill many predators unlucky enough to tangle with a porcupine.

The female will carry her young (gestate) for 93 to 112 days, and gives birth to one or two pups (sometimes up to four) in a grassy nest within the multichambered burrow. The 12-ounce (340-gram) pups have fur when they are born and can move on their own immediately. They nurse for three or four months, but after just a week the pup's quills begin to form and they may leave the nest with their mother. Old World porcupines reach sexual maturity at anywhere from nine to 18 months.

OLD WORLD PORCUPINES AND PEOPLE

Porcupines are hunted in many countries for their meat, which is considered a delicacy, and for their quills, which many cultures use for decoration and religious symbols. Because of their fondness for human-grown crops, they are also hunted as a pest species. Often infested with fleas and ticks, porcupines carry the sometimes deadly bubonic (byoo-BON-ik) plague and rickettsiasis, a potentially serious bacterial infection.

CONSERVATION STATUS

Although many porcupine species are extremely adaptable to changing environmental conditions, some are threatened, according to the World Conservation Union (IUCN). The Malayan porcupine is listed as Vulnerable, facing a high risk of extinction in the wild; and the thick-spined and North African crested porcupines are Near Threatened, not currently threatened, but could become so.

INDIAN CRESTED PORCUPINE (Hystrix indica): SPECIES ACCOUNTS

Physical characteristics: The Indian crested porcupine is known among the other Hystrix species for its ability to produce an especially loud rattle with its quills. It ranges in head-to-rump length from 27.6 to 35.4 inches (70 to 90 centimeters) and is the largest of the African porcupines, ranging from 24.3 to 39.7 pounds (11 to 18 kilograms). This species has a short, high head that features a prominent mane of quills on its head and neck that can be up to 16 inches (40 centimeters) long and which the animal can raise into a tall, threatening crest immediately. Its sides and back are covered with thick, cylindrical spines and its tail is layered with white, shorter quills. Each of the porcupine's feet is broad and has a thick, well-developed claw for digging burrows and finding food.

Geographic range: This porcupine is endemic throughout southwest and central Asia, including India, Bhutan, Nepal, Bangladesh, and Sri Lanka, and in some parts of the Middle East, such as Iran, Israel, and Saudi Arabia.

Habitat: This species prefers to live on rock-strewn hillsides to as high as 7,875 feet (2,400 meters), but can adapt to just about any environment. They also make homes in scrublands where trees are sparse and in grasslands and forests. Like most of the porcupine species, the Indian crested shelters in caves, crevices, or burrows they or other animals have dug. When used for a period of time, their burrows become quite complex, with multiple entrances, chambers, and exits.

Diet: Like its cousins, the Indian crested porcupine eats human-grown crops of almost all kinds, in addition to wild vegetation, carrion, small bugs and mammals, and bones or antlers. Except when parents are teaching their young to forage, the search for food is usually solitary. They seems to prefer wandering along roads or tracks, and have been observed traveling more than nine miles in a single nighttime foraging trip.

Behavior and reproduction: Females of this species carry their young for an average of 112 days before giving birth, usually in February or March, in a grass-lined nest to a litter of one to four pups. Most females have only one litter per breeding season. Adults form monogamous (muh-NAH-guh-mus) pairs and both care for the young during the three-and-a-half–month nursing period. Up to fifteen members of a family group will share one burrow.

Indian crested porcupine and people: This porcupine species is hunted as a source of food in many cultures, and its voracious appetite for human-grown crops makes it a major threat to agriculture. Its extensive burrowing is damaging in gardens and other landscaped areas, and run-ins with the porcupines can cause serious illness and injuries to domestic animals and humans.

Conservation status: The Indian crested porcupine is common throughout its range. Its ability to adapt to multiple habitats and environmental changes make it a hardy species. Hunting of the creatures, however, has all but eliminated them from areas heavily populated by humans. ∎

SOUTH AFRICAN PORCUPINE (Hystrix africaeaustralis): SPECIES ACCOUNTS

Physical characteristics: The South African porcupine is the biggest rodent in its native region, ranging in head-to-rump length from 2.3 to 2.8 feet (71 to 84 centimeters) and weighing from 39.7 to 66.1 pounds (18 to 30 kilograms). Females tend to weigh slightly more than males. Even among animals known for their sharp senses of smell and hearing, this species has exceptionally keen senses. Their bodies are stocky, with sharp quills up to 11.8 inches (30 centimeters) long emerging from among the course, black hair that covers them. Their spines, as in the other species, are even longer, reaching up to 19.7 inches (50 centimeters). The animals can voluntarily erect the crest of spines and quills on their backs and napes, which are colored in black and white bars. The quills on the tips of their tails are hollow at the ends, which cause them to make a startling whizzing sound when shaken. The South African porcupine has long whiskers and air-filled cavities in the facial area of its skull, while its nasal bones are larger than normal for a creature of its size. All of these are probably adaptations to help the porcupine find food more easily. The creatures walk with an alternating gait, as a dog or cat would. They can swim and climb trees well, and often live twelve to fifteen years even in the wild.

Geographic range: This porcupine is found only African countries south of the Sahara, not including the southwestern coastal desert.

Habitat: This species seeks out habitat with rocky outcroppings and hillsides, but may be found at elevations up to 11,480 feet (3,500 meters) where vegetation is abundant. It requires shelter during the day, and uses caves or other animals' abandoned holes for that purpose.

Diet: The South African porcupine uses its powerful claws to dig up tubers, roots, and bulbs of many kinds. They especially like such cultivated crops as sugar cane, pineapples, bamboo, melons, cocoa and oil palms, and corn, but also occasionally eat carrion and gnaw on bark and bones. This species has special microorganisms in its front large intestine and appendix that help digest tough plant fibers.

Behavior and reproduction: The animals dig out cavernous, extensive dens that can reach up to 65.6 feet (20 meters) in depth, with a 6.6-foot (2-meter) deep central living chamber. As many as six family members may live together in the den, and they sometimes use it for defensive purposes by running into an entrance and erecting its spines to make it difficult (if not impossible) for predators to pull them out.

Reaching sexual maturity at between eight and eighteen months, the South African porcupine is a devoted parent that cares for its young over the long term. Females are "in heat" (estrus) for thirty-five days, during which they mate with their chosen partner. This species usually has two litters a year, during the wettest months between March and April. Females gestate for 93 to 105 days, then give birth to one to four pups in the family's grass-lined nesting chamber. Although they can eat solid food from birth, the pups nurse for about 100 days. The female cannot conceive another litter for three to five months after her season's first litter is weaned, stops feeding on breast milk.

South African porcupine and people: This species is hunted for its meat in many locations where people consider it a delicacy, while the porcupine's destructive and voracious feeding habits make them the enemy of many farmers, gardeners, and landscapers.

Conservation status: The South African porcupine is not threatened anywhere in its range, although humans and large cats sometimes reduce populations significantly for a short time. ∎