Hemicentetes nigricepshighland streaked tenrec

Geographic Range

Highland streaked tenrecs are found in the eastern escarpment of Madagascar's central plateau, as far north as Manandoy and as far south as Fianarantsoa. (Garbutt, 2007; Marshall and Eisenberg, 1996)

Habitat

Highland streaked tenrecs are found in schlerophyllous and montane forests and adjacent areas at elevations of 1550 to 1800 m. They occur both in primary rainforests and in introduced forests of eucalyptus and pine. They are most commonly found at forest fringes on the central plateau edge and near cultivated fields and rice paddies. Although they are very similar, H. nigriceps and its close relative H. semispinosus, (lowland streaked tenrecs) generally do not live sympatrically. In Andringitra and Ivohibe Massifs, the only known areas where where their ranges overlap, these two species inhabit different elevations. Hemicentetes nigriceps occupies higher elevations, and its elevation range is the same regardless of range overlap with lowland streaked tenrecs. (Garbutt, 2007; Jolly, et al., 1984; Marshall and Eisenberg, 1996; Stephenson, et al., 1994)

  • Range elevation
    1550 to 1800 m
    5085.30 to 5905.51 ft

Physical Description

Highland streaked tenrecs are fairly slender, have a total body length of 120 to 160 mm and a weight of 70 to 160 g (average 100 g). They do not exhibit sexual dimorphism. They have a long, pointed snout and lack a tail. Their skull has an elongate rostrum and their dentition is reduced in size, which is most likely an adaptation to eating relatively soft invertebrates. Highland streaked tenrecs have barbed, detachable quills covering their body, which are more pronounced around the crown. They have thick fur located between their quills and are blackish-brown in color with longitudinal whitish streaks. Their crown and forehead are black, and their underparts are creamy-white and less spiny. Along the back of highland streaked tenrecs are sensory hairs similar to whiskers. There is a specialized area on their rear called the stridulating organ that is attached to approximately 11 non-detachable quills that are used for communication. Lowland streaked tenrecs are very similar in size, shape, and coloration to highland streaked tenrecs. Lowland streaked tenrecs, however, have yellower streaks, a stripe running from their crown to the tip of their snout, and less developed underfur, giving them a spinier look. (Garbutt, 2007; Gould and Eisenberg, 1966; Marshall and Eisenberg, 1996)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    70 to 160 g
    2.47 to 5.64 oz
  • Average mass
    100 g
    3.52 oz
  • Range length
    120 to 160 mm
    4.72 to 6.30 in

Reproduction

During courtship, a male highland streaked tenrec hisses loudly while approaching a female. He pushes his upturned snout into her cheeks and ears and into the quills on her body and nuchal crest, while continuing to hiss. If a female is unreceptive, she wards off the male by bucking her head, partially erecting her spine, and emitting a high-pitched chirp. If the female is receptive, she relaxes her quills and allows copulation. During copulation, a male's quills are erect over most of the body and his stridulating organ is very active. The stridulating organ of the female, however, is still. (Garbutt, 2007; Marshall and Eisenberg, 1996; Stephenson, et al., 1994)

Reproduction of highland streaked tenrecs varies but generally take place during the wet season (November to April). After a gestation period of 55 to 63 days, a litter of 2 to 8 is born. At birth, juveniles weigh around 8 g. Young develop very quickly; their eyes open within 7 to 8 days of birth, and they are weened within 18 to 25 days. Females reach sexual maturity at 35 to 40 days of age. (Garbutt, 2007; Marshall and Eisenberg, 1996; Stephenson, et al., 1994)

  • Breeding season
    Breeding of highland streaked tenrecs generally occurs during the wet season, November to April.
  • Range number of offspring
    2 to 8
  • Range gestation period
    55 to 63 days
  • Range weaning age
    18 to 25 days
  • Range age at sexual or reproductive maturity (female)
    35 to 40 days
  • Range age at sexual or reproductive maturity (male)
    35 to 40 days

Highland streaked tenrecs are altricial, so females provide food, shelter, and protection and groom their young until they are able to provide for themselves. Little is otherwise known regarding parental investment of highland streaked tenrecs. (Garbutt, 2007; Marshall and Eisenberg, 1996; Stephenson, et al., 1994)

  • Parental Investment
  • altricial
  • female parental care
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

Because most highland strekaed tenrecs are more commonly observed in captivity, little is known about their lifespan in the wild. In captivity, they generally live 2 years, though some have survived up to 3 years. (Gould and Eisenberg, 1966; Stephenson, et al., 1994)

  • Range lifespan
    Status: captivity
    2 to 3 years
  • Average lifespan
    Status: captivity
    2 years

Behavior

Highland streaked tenrecs are nocturnal, and their activity peaks 3 to 4 hours after darkness. Reductions in day length, food supply and ambient temperature induce torpor. Torpor is also affected by endogeneous rhythms and occurs more often between May and October when temperatures are higher. During torpor, highland streaked tenrecs sleep in a curled position on their backs or sides with their legs up. Usually the hind feet are kept away from the body while the forefeet are kept close to the chin. Sometimes the hind feet seem to swell with fluid. Highland streaked tenrecs may get up and scratch themselves, bite dirt from their toenails, or drink and eat while still in torpor. (Garbutt, 2007; Marshall and Eisenberg, 1996)

Home Range

Little information is available regarding the home range of highland streaked tenrecs.

Communication and Perception

Highland streaked tenrecs can communicate by using a group of specialized stridulating quills located on the center of their back. These spines vibrate, creating an ultrasonic sound, which sounds like dry grass being rubbed and crackled to the human ear. The pulsing sounds created by this organ are made up of broad band noise from about 2 to 200 kHz and can be detected by another tenrec more than 10 m away. Intensity and rate of stridulation vary based on social context or state of arousal. Motivation and position can be conveyed through stridulation. Mothers also use these sounds to encourage their dependent young to follow them. (Garbutt, 2007; Marshall and Eisenberg, 1996)

Highland streaked tenrecs also use a wide variety of vocal noises. During a defense reaction, a vocal buzz is emitted. During courtship, a male approaches the female while emitting a loud hiss, and females unreceptive to the male suitor emit a high-pitched squeak. In lab experiments, highland streaked tenrecs used tongue clicks as a form of echolocation. They also use their sense of smell to locate worms, but it is unknown to what extent upon which this is relied. (Garbutt, 2007; Marshall and Eisenberg, 1996)

Food Habits

Highland streaked tenrecs actively forage in leaf litter in areas where soil is damp, soft and shaded for earthworms and other soft-bodied invertebrates. They forage both individually and in groups. Highland streaked tenrecs may stomp with both forepaws on the ground to stimulate earthworm activity. When feeding, they pivot their rumps from side to side to ward off other tenrecs that may try to take the worms from them. Highland streaked tenrecs are very preoccupied when feeding and become much easier for humans to handle. In captivity, an otherwise aggressive tenrec was undisturbed by being handled when eating. (Garbutt, 2007; Marshall and Eisenberg, 1996)

  • Animal Foods
  • insects
  • terrestrial worms

Predation

Known predators of highland streaked tenrecs include fosa, fanaloka and ring-tailed mongoose, as well as large snakes like the Madagascar ground boa. When threatened or disturbed, highland streaked tenrecs emit a vocal buzz and raise the crest of spines on their head and body both laterally and forward. In an effort to embed the detachable barbed quills in a predator's snout, they turn to face the predator or cause of the disturbance, and buck violently, jumping up and down. If a predator touches a tenrec, their bucking becomes more violent. 'Humans Homo sapiens' occasionally hunt highland streaked tenrecs for food. (Garbutt, 2007; Marshall and Eisenberg, 1996)

Ecosystem Roles

Little information is available regarding the role of highland streaked tenrecs in their ecosystem. Because of their specialized diet, they may impact populations of earthworms and other soft-bodied invertebrates.

Economic Importance for Humans: Positive

Humans occasionally hunt highland streaked tenrecs for food.

  • Positive Impacts
  • food

Economic Importance for Humans: Negative

There are no known adverse effects of highland streaked tenrecs on humans.

Conservation Status

Highland streaked tenrecs are fairly abundant and are quite tolerant to human disturbance. They are listed as a species of least concern on the IUCN Red List.

Contributors

Luke McTighe (author), Michigan State University, Pamela Rasmussen (editor), Michigan State University, Tanya Dewey (editor), University of Michigan-Ann Arbor, Gail McCormick (editor), Animal Diversity Web Staff.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

echolocation

The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

food

A substance that provides both nutrients and energy to a living thing.

insectivore

An animal that eats mainly insects or spiders.

island endemic

animals that live only on an island or set of islands.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

ultrasound

uses sound above the range of human hearing for either navigation or communication or both

vibrations

movements of a hard surface that are produced by animals as signals to others

References

Garbutt, N. 2007. Mammals of Madagascar: A complete guide. London: Yale University.

Gould, E., J. Eisenberg. 1966. Tenrec Biology. Journal of Mammalogy, 47/4: 660-686. Accessed July 15, 2008 at Http://www.jstor.org/stable/1377896?seq=1.

Jolly, A., P. Oberle, R. Albignac. 1984. Key Environments: Madagascar. Oxford: Pergamon Press.

Marshall, C., J. Eisenberg. 1996. Hemicetetes semispinosus. American Society of Mammalogists, Mammalian Species No. 541: 1. Accessed July 15, 2008 at http://www.science.smith.edu/departments/biology/VHAYSSEN/msi/pdf/i0076-3519-541-01-0001.pdf.

Stephenson, P., P. Racey, F. Rakotondraparany. 1994. Maintenence and reproduction of tenrecs (Tenrecidae) at Parc Tsimbazaza, Madagascar. International Zoo Yearbook, 33: 194-201. Accessed July 15, 2008 at http://tenrec.lima-city.de/pjs94.htm.