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.
- Other Geographic Terms
- island endemic
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.
- Habitat Regions
- tropical
- Terrestrial Biomes
- rainforest
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.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
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.
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.
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
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.
- Parental Investment
- altricial
- female parental care
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
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.
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.
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.
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.
- Communication Channels
- acoustic
- Other Communication Modes
- vibrations
- Perception Channels
- tactile
- acoustic
- ultrasound
- echolocation
- chemical
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.
- Primary Diet
-
carnivore
- insectivore
- vermivore
- 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.
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.
Additional Links
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.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- island endemic
-
animals that live only on an island or set of islands.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- 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
- 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.
- female parental care
-
parental care is carried out by females
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- social
-
associates with others of its species; forms social groups.
- acoustic
-
uses sound to communicate
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- ultrasound
-
uses sound above the range of human hearing for either navigation or communication or both
- 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.
- chemical
-
uses smells or other chemicals to communicate
- food
-
A substance that provides both nutrients and energy to a living thing.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- 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.
- 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.
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 .