Tenrec ecaudatus
tailless tenrec

The common tenrec occurs on Madagascar and on the Comoro Islands, between Madagascar and Africa. It has been introduced on Reunion, Mauritius, and the Seychelle Islands.

Tenrec ecaudatus is generally found near water sources in areas with ample brush and undergrowth for cover. It seems to be equally common in inland plateaus and coastal humid forests throughout Madagascar, but it is absent in the arid southwestern districts. Generally, the common tenrec is found in the eastern rainforests and in the gallery forests that border the river systems of the west. These animals are very common near paddy fields.

Tenrec ecaudatus is one of the largest living insectivores. Head and body length ranges from 265 to 390 mm. The coloration of the common tenrec varies geographically from grey-brown to red-brown. Pelage is not dense and is a combination of hairs and blunt spines. The young have rows of white spines in longitudinal rows along their backs; these are replaced in the adult by a mane of stiff long hairs. The forelimbs are longer than the hindlimbs. The skull is cylindrical and the snout elongated. Females generally have 12 nipples, but up to 29 have been recorded.

Common tenrecs are usually solitary, but during the austral breeding season (October to November) male-female encounters often lead to brief physical contact (i.e. nose-to-rump, nose-to-nose, nose-to-side, nose-to-cloaca, nose-to-ear) and then mating. The male often licks the female and grasps her with his forelimbs to copulate.

Gestation lasts 56 to 64 days. Young are born in the wet months of December and January, when the number of invertebrates is at a maximum. It is thought that only one litter per year is usual, but the presence of small young in March suggests that a second litter is possible if the first litter dies after birth. Litter size ranges from 1 to 32, the extreme for mammals. The average litter size varies with habitat type; average size is 10 in the Seychelles rainforests near the equator, 15 in most rainforest areas examined, and 20 in seasonal woodland and savanna regions.

At birth the young are fairly undeveloped, but are less altricial than the newly born young of most insectivores. Their eyes open between 9 and 14 days. At three weeks the young begin to forage with their mother, following her in a more-or-less straight line. Like their mother, they gather and carry nest materials in their mouths. They begin to nurse less and to take solid food at approximately four weeks. The young molt their characteristic stripes at 36 days, and leave the nest shortly after. They often forage together for a period after dispersing from the nest.

A captive common tenrec lived for 59 months.

The common tenrec is a solitary animal and attempts to avoid conspecifics; with the exception of mother and young. Tenrec ecaudatus forages and hibernates alone. Males that meet during the breeding season will fight one another. Common tenrecs have two major daily activity periods, the first from 1800 to 2100 hours and the second from 0100 to 0500 hours. It is not unusual to see tenrecs swimming in rice paddies during their forays. They will climb steep rock faces when seeking food, but it is uncommon to see them in trees.

The burrows of the common tenrec are usually near streams and are of two distict types. A hibernating burrow is between one and two meters long. The single entrance is plugged with soil during the period of torpor. The burrows of active common tenrecs are quite different; a Y-shaped opening provides two open exit routes. The burrows serve the animals as buffers to extreme temperatures. Tenrecs hibernate during the dry autumn months of May through September, when resources are limited. During this period of torpor, their bodies are cold to the touch.

These animals cover 0.5 to 2 hectares per night in search of food. Receptive females, however, range over only around 200 square meters; it has been hypothesized that decreasing the foraging range may increase the likelihood of being found by a male.

When threatened or angered the common tenrec erects the ridge of long hairs on its back and vocalizes with hisses, squeaks, squeals, and "piff" sounds. If an animal is surprised in its nest it will display its truly enormous gape. If startled in the open it can run quickly to cover. Disturbed young tenrecs produce an audible alarm signal through a process called stridulation, in which bristles on the midback are rubbed together. Hearing this sound may cause littermates to scatter and run. Stridulation may also help the young to locate one another or the mother to locate her young.

One of the most important of the common tenrec's senses may be the long whiskers and the sensitive hairs on the back; these are used to detect vibrations. The common tenrec's eyesight is better than that of most tenrecids and may also be an important sense. In addition, observations of captive T. ecaudatus scent-marking by dragging its cloaca on the ground indicate that scent is an important form of communication in these animals.

Tenrec ecaudatus is omnivorous and eats some vegetation, fruit, reptiles, amphibians, and small mammals in addition to its main diet of invertebrates. These tenrecs probe fissures in rocks and logs with the snout and detect prey with long, sensitive whiskers. They capture and kill with the mouth.

Increased energy requirements during lactation necessitate feeding during daylight hours. It is thought that the stripes of the young and the dark coloration of the female function in camouflaging them during daytime foraging.

The common tenrec has been an important food source for the human inhabitants of Madagascar for thousands of years. In addition, as an insectivore it undoubtedly reduces the numbers of insect pests.

This species is reported to be common on Madagascar, and is not generally believed to be in need of special conservation efforts. Introduced rats (genus Rattus) may compete with the common tenrec in some circumstances. The IUCN rates the species as being of "Least Concern," it's lowest category, and the species is not listed in the CITES treaty.