TENRECS – Tenrecidae

TENREC

TENREC FACTS

Rat- or shrew-like in general appearance, tenrecs vary greatly in body size, tail length, and color. One of the most consistent features is the long, pointy snout that is typically adorned with long whiskers. The smallest tenrecs have head and body lengths of just 2 inches (5.5 centimeters) and weights of 0.14 ounces (4 grams), while the largest can reach 14 inches (35.7 centimeters) and weigh up to 44 pounds (2 kilograms). Tails vary from tiny, unnoticeable stubs to long and very obvious structures stretching up to three times the length of the body.

Some species have soft yellow to brown fur, and a few have vivid black-and-white or yellow-and-black fur patterns. Adults in several species have sharp spines that are quite effective in thwarting attacks by would-be predators. Some youngsters, like the common tenrec, have blunt spines that produce a sound when rubbed together.

GEOGRAPHIC RANGE

Tenrecs live in Madagascar and western central Africa.

Introduced to Comoros, Mascarenes, and Seychelles, which are islands in the Indian Ocean.

HABITAT

Most species live in humid forests or in grasslands. A few species can survive well in marshy areas, drier forests, or agricultural fields. Aquatic tenrecs and otter shrews spend much of their time in or near freshwater streams.

WHAT DO TENREC EAT?

The tenrec diet varies considerably among species. For the most part, the land-living tenrecs eat insects, worms, and other invertebrates (animals without backbones). A few will also devour baby mice and other small vertebrates (animals with backbones), and some will even munch on dead animals they come across. The tenrecs that live in marshes, near streams, or in the water dine on other water-loving creatures, like aquatic insects, frogs, fishes, mollusks, and crabs.

BEHAVIOR AND REPRODUCTION

Scientists have few details about many species of tenrecs, partly because the animals are relatively small and are typically only active at night. They rest during the daytime, often in tunnels that they construct. Some, like the Ruwenzori otter shrew, sleep on beds of grass in the tunnels. During their daily rest, several species are known to enter a state of deep sleep, called torpor, which allows them to conserve their energy. One species, known as the large-eared tenrec, is particularly tuned in to the outdoor temperature, and its internal body temperature quite closely matches the outdoor temperature. When weather becomes cool, its body temperature takes a similar dip, and the animal may enter torpor. In long, dry periods, some species take an extended deep sleep, called estivation (est-ih-VAY-shun), during which the heart rate and body temperature fall and the animal needs to burn far less energy to stay alive. Estivation may last days or even weeks.

Tenrecs that estivate for longer periods will frequently plug the openings of their burrows in preparation for the extended sleep.

Adults likely spend most of their lives alone, coming together only for mating. Sometime, males will remain with the female while she’s pregnant, a span that typically lasts about two months. A few reports suggest that some male-female pairs may remain together during other times of the year, too. Overall, scientists know little about mating rituals in most species, but they have observed some behaviors. In the hedgehog tenrec, for example, the females give off an odor during mating season that causes a milky substance to flow from glands near the eyes of males. Each year, females have one litter of one to thirty-two babies, depending on the species. The young, most of which are born blind and naked, apparently stay with the mother for at least four or five weeks, and possibly more.

TENRECS AND PEOPLE

Of all the tenrec pet, the most popular is perhaps the greater hedgehog tenrec, which has become quite a popular pet. In Madagascar, which has a thriving tenrec community, humans have traditionally viewed the animals as a source of prime meat, and enthusiastically hunted them. Humans also hunt the giant otter shrew for its pelt.

CONSERVATION STATUS

Ten species are at risk, according to the Red List of the World Conservation Union (IUCN). One, the tree shrew tenrec, is listed as Critically Endangered, facing an extremely high risk of extinction, or dying out; six are Endangered, facing a very high risk of extinction; and three are listed as Vulnerable, facing a high risk of extinction. Many of these species exist in small areas and are threatened by human activities that are changing their habitat. For example, the aquatic tenrec is an Endangered species that is found in only a few spots in Madagascar. It needs clean rivers to survive, but agriculture and deforestation are either eliminating the rivers or allowing silt to muddy up the waters.