Setifer setosus

Geographic Range

Greater hedgehog tenrecs are found throughout the island of Madagascar and are endemic to this island.

• Biogeographic Regions
• ethiopian ethiopian
  • native native

• Other Geographic Terms
• island endemic island endemic

Habitat

The island of Madagascar ranges from sea level to 2,250 meters above sea level, and Setifer setosus is found throughout the island, with the exception of wetlands and marshes. Greater hedgehog tenrecs are seen in urban areas and even in areas with extensive human disturbance. The prime habitat for greater hedgehog tenrecs are the eastern forests and lower elevations because of their eating habits, but they are found in wet and dry areas.

• Habitat Regions
• temperate temperate
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• forest forest
• scrub forest scrub forest

• Other Habitat Features
• urban urban
• suburban suburban
• agricultural agricultural

Physical Description

Greater hedgehog tenrecs may seem similar to hedgehogs ( Erinaceidae ), but they are tenrecs ( Tenrecidae ), which are distantly related. Greater hedgehog tenrecs have a round muzzle and white-tipped, sharp spines that densely cover their back, sides, and tail. They vary in color depending on their location: they can be light colored or blackish, with dark brown or whitish soft hairs covering their limbs and ventral surface. Greater hedgehog tenrecs have relatively long whiskers. They weigh 6.3 to 9.5 ounces. They are 6 to 8.6 inches long, and have a half-inch long tail. The dental formula for S. setosus is: 3/3, 1/1, 2/2, 3/3. Sexes cannot be differentiated by size. Lactating females have 5 pairs of prominent nipples.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Greater hedgehog tenrecs have been poorly studied because they are nocturnal and cryptic. They are promiscuous, seasonal breeders. Males may use chemical communication to signal sexual readiness, this consists of a white substance that is secreted from their eyes.

• Mating System
• polygynandrous (promiscuous) polygynandrous (promiscuous)

The breeding season begins shortly after emergence from hibernation in late September to mid-October and lasts until just before greater hedgehog tenrecs re-enter hibernation in April. The length of the breeding interval is unknown. During a breeding season, 1 to 5 young may be born. The gestation period ranges from 51 to 65 days. In captivity, 3 days after birth, the young weigh approximately 20 grams and measure a length of 75 mm. Lactation extended until 3 weeks after birth in captive individuals, after which females show a decline in interest towards the young. At approximately 14 days old, young accompanied the female outside of the nest during her trips to the food dish to learn the route back to the nest, but this period only lasted about 3 days. The age at which the young reach sexual or reproductive maturity is unknown.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous

During the week of parturition, female shows increased nest building behavior. After birth, maternal behavior consists of licking young, huddling over them while they nurse, and an increased defensive behavior if nest is disturbed.

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

Lifespan/Longevity

Greater hedgehog tenrecs have been studied very little, despite their abundance throughout Madagascar. The longest observed lifespan in captivity has been 14.1 years.

Behavior

Greater hedgehog tenrecs are nocturnal. They enter a daily torpor and a seasonal torpor, or hibernation. They nest in shallow holes in the ground or in tree cavities during the day so that they are out of visual range. They have the ability to roll into a ball, tuck their head and limbs towards their body, and enclose themselves into an impermeable shield of spines.

• Key Behaviors
• terricolous
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• hibernation hibernation
• daily torpor
• solitary solitary

Home Range

Greater hedgehog tenrecs are found throughout the island of Madagascar and their home range is large for a relative small mammal. In males, the average range is 13.7 +/- 4.9 ha. In females, the average range is 6.7 +/- 2.0 ha.

Communication and Perception

Greater hedgehog tenrecs may communicate by grunts, squeaks, and chirps. A grunt will occur when an individual isn’t highly motivated, but does not want to be contacted. A squeak will occur with a mild disturbance. A chirp will occur at mating, most frequently made by a female when the male first mounts. A ‘pouf-pouf’ and hissing sound will occur during offensive and defensive behaviors. When greater hedgehog tenrecs touched, they will curl into a ball with their spines pointed out in all directions, or they will jump and scratch with their spines. The males secrete and white substance from their eyes which may be chemical communication related to sexual readiness. Greater hedgehog tenrecs will also place feces and urinate outside their burrows, which may signal territoriality.

• Communication Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Greater hedgehog tenrecs are omnivores. They eat insects, grubs, and other invertebrates and are eat fruits and will scavenge. They forage at ground level, although they are also known to climb.

• Primary Diet
• omnivore omnivore

• Animal Foods
• carrion carrion
• insects
• terrestrial non-insect arthropods
• mollusks

• Plant Foods
• fruit

Predation

There are no major threats to greater hedgehog tenrecs, although they are locally threatened by overhunting in some parts of their range. To protect themselves, they have the ability to roll into a ball, tuck their heads and limbs towards their body, and enclose themselves into an impermeable shield of spines. They will also defecate and urinate if they are disturbed, which can serve as a predator deterrent. Specific cases of predation on greater hedgehog tenrecs are not reported, but they may be preyed on by snakes or birds of prey.

Ecosystem Roles

Although greater hedgehog tenrecs are one of the largest and most common species of tenrec, they are poorly studied. Greater hedgehog tenrecs are insectivores as well as frugivores. In the process of eating fruit, they could disperse seeds.

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

Greater hedgehog tenrecs are used for food and have the potential to be seed dispersers, although this has not been studied. Greater hedgehog tenrecs are highly valued as food because of their high fat content. If greater hedgehog tenrecs are seed dispersers, humans can benefit from this as it helps promote new growth of fruit-bearing plants.

• Positive Impacts
• food food

Economic Importance for Humans: Negative

There are no known adverse effects of Setifer setosus on humans.

Conservation Status

Greater hedgehog tenrecs are considered "least concern" by the IUCN as their populations are large and they are found in a wide variety of habitats throughout Madagascar.

Additional Links

Encyclopedia of Life

Contributors

Rachel Owens (author), Northern Michigan University, John Bruggink (editor), Northern Michigan University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

Garbutt, N. 2007. Mammals of Madagascar: A Complete Guide . United States: Yale University Press. Accessed January 31, 2013 at http://books.google.com/books?id=ftjKjbPKF2oC&printsec=frontcover#v=onepage&q&f=false .

Gould, E., J. Eisenberg. 1966. Notes on the Biology of the Tenrecidae. Journal of Mammalogy , 47/4: 660-686. Accessed January 31, 2013 at http://www.jstor.org/stable/1377896?seq=2 .

Harris, M., L. Olson, W. Milsom. 2004. The Origin of Mammalian Heterothermy: A Case for Perpetual Youth?. Pp. 142-152 in Life in the Cold: Evolution, Mechanisms, Adaptation, Application , Vol. 27. University of Alaska Fairbanks, Alaska, USA.: Biological Papers of the University of Alaska. Accessed January 31, 2013 at http://mercury2.iab.uaf.edu/michael_harris/publications/HarrisOlsonMilsomWCover.pdf .

Levesque, D., D. Rakotondravony, B. Lovegrove. 2012. Home range and shelter site selection in the greater hedgehog tenrec in the dry deciduous forest of Western Madagascar. Journal of Zoology , 287/3: 161-168. Accessed January 31, 2013 at http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2012.00899.x/full .

Rand, A. 1935. On the Habits of Some Madagascar Mammals. Journal of Mammalogy , 16/2: 89-104. Accessed January 31, 2013 at http://www.jstor.org/stable/1374353?seq=1 .

2012. "IUCN Red List of Threatened Species" (On-line). Setifer setosus. Accessed January 31, 2013 at www.iucnredlist.org .

2012. Setifer setosus. Encyclopedia of Life . Accessed January 31, 2013 at http://eol.org/pages/1178675/details .

2012. "Small Mammals: Greater Madagascar Tenrec" (On-line). Smithsonian National Zoological Park. Accessed January 31, 2013 at http://nationalzoo.si.edu/animals/smallmammals/fact-greatertenrec.cfm .

2004. Tenrecs (Tenrecidae). Pp. 225-235 in Grzimek's Animal Life Encyclopedia , Vol. 13, 2nd Edition. Detroit: Gage. Accessed January 31, 2013 at http://go.galegroup.com/ps/i.do?action=interpret&id=GALE|CX3406700816&v=2.1&u=lom_nmichu&it=r&p=GVRL&sw=w&authCount=1 .

Smithsonian Institution Press. The Tenrecs: A study in Mammalian Behavior and Evolution. City of Washington: United States Government Printing Office. 1969. Accessed January 31, 2013 at http://si-pddr.si.edu/jspui/bitstream/10088/5115/2/SCtZ-0027-Lo_res.pdf .