Friday, 
November 13, 2015

The Point of Porcupines

Image
green placeholder image
Trundling about by night, seeking food and trying to avoid confrontation, prickly porcupines seem like they are on a mission. The word porcupine comes from the Latin porcus for pig and spina for spine—therefore, “spiny pig.” Porcupines, however, are rodents and not related to pigs. Like all rodents, the porcupine’s front incisor teeth grow continuously throughout its life and need to be worn down by gnawing. The teeth are orange or red because they are coated with iron-rich enamel, not white enamel like ours. Whether in the trees or on the ground, these lumbering, rounded creatures are pointedly unmistakable. About two dozen porcupine species span the globe and form two geographic families in the New World and Old World. They vary significantly from each other and are not closely related—their signature quills evolved independently! They range in size from the dainty Rothchild’s porcupine of Panama weighing just over 2 pounds to the hefty North African crested porcupine, which tips the scale at around 75 pounds. While porcupines differ greatly among species, they are considered the third-largest rodent in the world behind the capybara and beaver. The plethora of porcupine species are mostly named for some obvious physical characteristic, be it brush-tailed, bush-tailed, crested, dwarf, long-tailed, prehensile-tailed, stump-tailed, or hairy.

Quill Seeker

The common denominator between porcupine species is, of course, their coat of sharp spines, which are stiff, keratin-coated hairs often containing barbs that penetrate an enemy’s skin and require some skill to remove. The quills cover the animal, except for its face and belly. An individual porcupine can have over 30,000 quills! The thorny covering is actually one of three layers: porcupines also have fur underneath for warmth and soft guard hairs interspersed among the quills. Even the quills have variable thickness, color, and length. Old World porcupines are larger in size and their quills are longer and grouped in clusters. In contrast, New World porcupines are a bit smaller and their quills, some at a pokey two to four inches long, are attached individually. [caption id="attachment_129591" align="aligncenter" width="1400"] STICKING AROUND
Porcupine quills are essentially hair with a stiff keratin coating. Being hollow makes them lighter for the animal to “wear” and keeps the animal more bouyant in water.[/caption] While porcupines can grow back quills that fall out or get stuck in another creature’s skin, they cannot “shoot” their quills at adversaries. Usually, the quills lie flattened against the animal’s body until a threat is perceived. When alarmed, the quills spring erect, making the animal appear much larger and less appetizing. Some porcupines quiver and shake hollow quills near their rump in a menacing warning. If the predator does not retreat, the porcupine emits a smelly odor, chatters its teeth, and stamps its rear feet. If that doesn’t work, the animal will back up toward the enemy with its quills ready to spear the foe. This usually does the trick, as the quills are sharp, barbed, painful, and debilitating. Few animals are willing to take that on.

North American Porcupine

Also called the Canadian porcupine or the common porcupine, this adaptive rodent lives in forest, grassland, desert, and shrub areas in most of Canada, Alaska, western and northern US, and northern Mexico, making a cozy home in caves, tree hollows, or other natural shelters. It doesn’t hibernate, but will remain in its den during inclement weather. These porcupines eat leaves, twigs, and plants like clover and even skunk cabbage; they devour inner layers of tree bark in the winter months, earning the wrath of forest managers and Christmas tree growers. [caption id="attachment_129586" align="aligncenter" width="1400"] AMAZING MAIZEY
(Left) Maizey is a North American porcupine, one of about two dozen porcupine species from around the world. (Right) A porcupine’s teeth grow continuously for life, so gnawing is important. Iron-rich enamel gives their teeth an orange or red tint.[/caption] Porcupines have an urgent need for salt and will stop at nothing to get it, including seeking out natural salt licks, glue that bonds plywood together, human perspiration on tools, road salt on the undercarriage of vehicles, and even some paints. They gnaw on antlers and bones of dead animals for sodium and other necessary minerals. The North American porcupine is usually brownish or gray in color, with short, dense quills. Like all porcupines, it is largely nocturnal. In addition to its climbing skills, it is also a good swimmer and its hollow quills help it remain buoyant.

Porcupines at the Zoo

The Children’s Zoo is home to Maizey, a two-year-old North American porcupine Erethizon dorsatum, and Icana, a Brazilian porcupine Coendou prehensilis. Maizey is a good-sized creature, even when her quills are lying flat. “She’s very curious and also stubborn,” said Kristen Craig, senior keeper. Fortunately, she is food driven, so when keepers need to move her into a crate, she can usually be coaxed with a tasty piece of fruit or corn. Kristen noted that North American porcupines are more prone to seasonal “mood changes” than porcupines from more tropical areas. “If it’s chilly out, Maizey may not cooperate,” she said. In contrast, Icana, named for a river in South America, is more agreeable. Also called a prehensile-tailed porcupine, this species has short, dense quills and wraps its tail around branches to help stabilize it during feeding or slumber. [youtube video=ttps://youtu.be/y_8375JT1yo] Icana is relationship-driven, and happy to cooperate with keepers she trusts. She has been trained to “step on your hand, and we hold her tail, which does not have quills,” explained Kristen, so keepers can safely move her when needed. “She also has the cutest nose of any animal in the Zoo,” insists Kristen. With long claws and a prehensile tail, this species is well equipped for an arboreal lifestyle; keen senses of smell, touch, and hearing all conspire to make this porcupine a successful nocturnal creature. Once darkness cloaks the forest, they forage for food slowly but deftly through the trees and dine on bark, leaves, fruit, buds, and roots. Once a tree’s resources are exhausted, the animal descends to the ground to find another tree to climb.

Crested Porcupines: the Bone Catchers

Old World crested porcupines inhabit mainland Italy, Sicily, North Africa, and sub-Saharan Africa. They can reach 75 pounds and about 33 inches in length. As the world’s largest porcupine, the mighty African crested porcupine Hystrix cristata sports long, luxuriant, banded quills forming a dramatic “crest” down its back. Distinct among Old World porcupines is a shorter tail and the presence of hollow “rattle quills” that create a hiss-like warning. It is a formidable-looking animal from any angle! Crested porcupines rarely climb trees, but surprisingly they are good swimmers. They are mostly nocturnal and usually monogamous. On their nighttime forays, they have been known to collect thousands of bones and store them in a cache for future gnawing. This species is illegally hunted despite being strictly protected under international and domestic law. According to the IUCN, it is considered a pest in parts of its range, since these porcupines enjoy “harvesting” corn, pumpkins, sweet potatoes, cassava, young cotton plants, and rubber trees. They are also collected for human consumption in Italy, North Africa, and sub-Saharan Africa, while in Morocco the porcupine is widely used for traditional medicine and witchcraft and commonly found in local markets. Nevertheless, this species is holding on across its range and dodging endangered status.

Pokie at the Park

Senior animal trainer Donna Kent has worked with Pokie, the South African crested porcupine at the Safari Park, for almost 20 years and insists she is the nicest porcupine you’ll ever meet. “She’s even cuddly!” When Donna sits in Pokie’s enclosure to do paperwork, the animal leans against her—quills flat—and even nestles under her knees. “She loves to have her ears rubbed and ‘grooms’ me back by licking.” Pokie is a self-trained litter box user and enjoys walking on a harness around the Park. Donna described Pokie as extremely intelligent and quick to learn. To wear her harness, Pokie does a “mark up” behavior by placing her front feet on a stump as Donna slips the harness over her head—and flips the quill crest over the harness. After a yoga-like stretch and stunning quill flare, Pokie waddles over to the scale, where her 34.6 pounds of charm is duly noted. Donna has never been aggressively jabbed with her quills, but “You better pay attention when walking her in case Pokie stops—you don’t want to bump into her!” Pokie is part of the Park’s Behind-the-Scenes Safaris and visitors can see her up close. “Rodents get a bad rap,” said Donna. “But porcupines are diverse and smart. Quills are an incredible and unique defense—these animals are well protected!” Pokie proceeds to grasp a four-inch cob of corn in her front paws and mow across it back and forth, chattering contentedly. Pokie’s one porcupine that knows how to make a point!