Rhynchocyon petersiblack and rufous elephant-shrew(Also: black and rufous sengi)

Geographic Range

Black and rufous elephant shrews (Rhynchocyon petersi) are endemic to central and eastern Africa. They are found in altitudes ranging from sea level to 2,300 meters and are found almost exclusively in Tanzania, in the Udzungwa Mountains. Strangely, there are no species of elephant shrews in western Africa or the Sahara region. (Coster and Ribble, 2008; Rathbun, 2009)

Habitat

Like most giant elephant shrews, black and rufous elephant shrews live in lowland forests and dense woodlands. They reside in undisturbed forests, where they keep large territories and make nests on the ground from leaf litter. Black and rufous elephant shrews rely on bugs found under this leaf litter for food. (Coster and Ribble, 2008)

  • Range elevation
    0 to 2300 m
    0.00 to 7545.93 ft

Physical Description

Black and rufous elephant shrews are small mammals with long proboscises, used to turn over leaf litter and dig up beetles, and a long tongue to scoop up bugs. They have multi-colored pelage, their front half is covered in reddish-brown fur, while their back half is covered in black fur. Adults weigh 350 to 700 grams, with head and body lengths of up to 310 mm and tail lengths of up to 250 mm. Because they are often predated upon, they need to move rapidly; therefore their hindlimbs are much longer than their forelimbs. (Coster and Ribble, 2008; Rathbun and Woodall, 2002; Rathbun, 2009; Smit, et al., 2011)

  • Sexual Dimorphism
  • sexes alike
  • male larger
  • Range mass
    350 to 700 g
    12.33 to 24.67 oz
  • Range length
    250 to 310 mm
    9.84 to 12.20 in

Reproduction

Black and rufous elephant shrews, similar to many elephant shrews, live in monogamous pairs with defined territories. Each animal can make and maintain up to ten nests in one territory, with several nests in use at one time. However, the pair bond is weak; the animals spend relatively little time in coordinated activities, except when a female is in estrus. Males are territorial, especially during the breeding seasons. This species may only be monogamous due to male guarding. (Coster and Ribble, 2008; Rathbun and Rathbun, 2006)

Mating is about the only time black and rufous elephant shrews make contact with conspecifics. Mating often occurs during a very short period of time. As with all elephant shrews, black and rufous elephant shrews give birth to one or two offspring at a time litters of three or four are very rare. Although most elephant shrews are born quite precocial, the young of giant elephant shrews are less precocial and are not ready to leave the nest until about two to three weeks after birth. Little information is available regarding the specific breeding information of black and rufous elephant shrews, however, their close relative, golden-rumped elephant shrews (Rhynchocyon chrysopygus), have about a 42-day gestation period and a 15-day weaning period, with about 4.5 litters per year. (Rathbun, 2009; Tacutu, et al., 2013)

  • Range number of offspring
    1 to 4
  • Average number of offspring
    2
  • Range time to independence
    2 to 3 weeks

Females do not spend much time with their litter, sometimes visiting them as little as once a day for a brief nursing period. No direct paternal investment in neonates has been documented. (Rathbun, 2009)

Lifespan/Longevity

As black and rufous elephant shrews are rarely observed in the wild, little is known of their lifespan. However, their close relative, golden-rumped elephant shrews (Rhynchocyon chrysopygus), may live up to 5 years in the wild and up to 11 years in captivity. (Tacutu, et al., 2013)

Behavior

As prey species, black and rufous elephant shrews are particularly skittish mammals, spending a large majority of their time either running from predators, or using their acute sense of hearing and smell to watch out for predators. Black and rufous elephant shrews are not social animals, members of genus Rhynchocyon spend their nights, and sometimes short periods of the day, alone in leaf nests on the forest floor. Because of this lack of social activity, the pairs do not often come in contact with one another. Home ranges may overlap, although, neighboring pairs rarely intersect territories, which suggests territoriality. Even though pairs are monogamous, males will express temporary polygamy if a neighboring male dies. Black and rufous elephant shrews also have pedal scent glands that are probably used in marking territory, or during cursorial activity. (Rathbun, 2009)

Home Range

Black and rufous elephant shrews have defined territories where each animal can make and maintain up to ten nests, with several nests in use at one time. Thus, territories are fairly large, although their home range size has not been documented. (Coster and Ribble, 2008)

Communication and Perception

Black and rufous elephant shrews spend very little time near conspecifics, due in part to male territoriality, therefore, these animals do not communicate often. Vocalizations are not common, but black and rufous elephant shrews sometimes foot drum or tail slap in stressful situations. These animals also scent mark their territories with perianal, sternal, subcaudal or pedal glands. Black and rufous elephant shrews also have acute senses of sight, sound and smell. (Rathbun and Woodall, 2002; Rathbun, 2009)

Food Habits

Elephant shrews are mostly insectivorous, which supported their inclusion in the now defunct order Afrosoricida. Nevertheless, their relatively hypsodont dentition suggests that at one time, elephant shrews may have had an herbivorous diet. Black and rufous elephant shrews strictly eat invertebrates, using their long proboscis to dig up insects under leaf litter. Likewise, their relatively long tongues are used to flick insects into their mouths. Ants and termites make up a large majority of their diet, however, black and rufous elephant shrews will eat just about anything they find on the forest floor, so long as it is small enough to fit in their mouth. (Coster and Ribble, 2008; Rathbun, 2009)

  • Animal Foods
  • insects
  • terrestrial non-insect arthropods
  • terrestrial worms

Predation

Elephant shrews are preyed upon by raptors, snakes and sometimes humans. When pursued, black and rufous elephant shrews take refuge in hollow logs, tree trunks or shallow burrows. Black and rufous elephant shrews have acute senses of sight, sound and smell, which are key in avoiding predators. Their hind limbs are also much longer than the forelimbs, which helps them quickly flee predators. Black and rufous elephant shrews use a certain gait when they are pursued by a predator, similar to the behavior of some ungulates. (Rathbun, 2009; Rovero, et al., 2008; Smit, et al., 2011)

Ecosystem Roles

Because they use their long snout for digging through leaf litter, black and rufous elephant shrews may aid nutrient turnover, which may in turn aid plant growth. These animals may also act as indicators of a healthy forest ecosystem and host a wide variety of parasites. (Coster and Ribble, 2008; Fourie, et al., 2008; Rathbun, 2009)

Economic Importance for Humans: Positive

These animals provide very little positive economic impacts; however, they are sometimes hunted for subsistence by the people native to the Udzungwa Mountains. (Rathbun, 2009)

  • Positive Impacts
  • food

Economic Importance for Humans: Negative

At this time, there are no known negative economic impacts of black and rufous elephant shrews.

Conservation Status

Black and rufous elephant shrews are listed as 'vulnerable' on the IUCN red list (IUCN), this status is probably due to deforestation and fragmentation of their habitat. (Rathbun, 2009)

Contributors

Abby Jacques (author), Northern Michigan University, John Bruggink (editor), Northern Michigan University, Leila Siciliano Martina (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

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

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.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

insectivore

An animal that eats mainly insects or spiders.

monogamous

Having one mate at a time.

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.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

semelparous

offspring are all produced in a single group (litter, clutch, etc.), after which the parent usually dies. Semelparous organisms often only live through a single season/year (or other periodic change in conditions) but may live for many seasons. In both cases reproduction occurs as a single investment of energy in offspring, with no future chance for investment in reproduction.

sexual

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

soil aeration

digs and breaks up soil so air and water can get in

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

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

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

young precocial

young are relatively well-developed when born

References

Asher, R., G. Olbricht. 2009. Dental Ontogeny in Macroscelides proboscideus (Afrotheria) and Erinaceus europaeus (Lipotyphla). Journal of Mammalian Evolution, 16/2: 99-115.

Coster, S., D. Ribble. 2008. Density and cover preferences of Black-and-rufous elephant-shrews (Rhynchocyon petersi) in Chome Forest Reserve, Tanzania. Journal of Zoology, 274/2: 126-133. Accessed January 31, 2013 at http://www.natuurwetenschappen.be/en/institute/associations/rbzs_website/bjz/back/pdf/BJZ%20135%28s1%29/Volume%20135%28s1%29,%20pp.%20175-177.pdf.

Fourie, L., J. Du Toit, D. Kok, I. Horak. 2008. Arthropod parasites of elephant-shrews, with particular reference to ticks. Mammal Review, 25/1-2: 31-37. Accessed April 15, 2013 at http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2907.1995.tb00435.x/abstract.

Nishihara, H., Y. Satta, J. Thewissen, M. Stanhope, N. Okada. 2005. A Retroposon Analysis of Afrotherian Phylogeny. Molecular Biology and Evolution, 22/9: 1823-1833. Accessed February 01, 2013 at http://mbe.oxfordjournals.org/content/22/9/1823.short.

Rathbun, G., C. Rathbun. 2006. Social structure of the bushveld sengi (Elephantulus intufi) in Namibia and the evolution of monogamy in the Macroscelidea. Journal of Zoology, 269/3: 391-399. Accessed February 01, 2013 at http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2006.00087.x/abstract.

Rathbun, G. 1979. Rhynchocyon chrysopygus. American Society of Mammalogists, 117: 1-4. Accessed February 01, 2013 at http://www.jstor.org/stable/10.2307/3503789.

Rathbun, G. 2009. Why is there discordant diversity in sengi (Mammalia: Afrotheria: Macroscelidea) taxonomy and ecology?. African Journal of Ecology, 47/1: 1-13. Accessed January 31, 2013 at http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2028.2009.01102.x/full.

Rathbun, G., P. Woodall. 2002. A bibliography of elephant-shrews or sengis (Macroscelidea). Mammal Review, 32/1: 66-70. Accessed February 01, 2013 at http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2907.2002.00092.x/full.

Rovero, F., G. Rathbun, A. Perkin, T. Jones, D. Ribble, C. Leonard, R. Mwakisoma, N. Doggart. 2008. A new species of giant sengi or elephant-shrew (genus Rhynchocyon) highlights the exceptional biodiversity of the Udzungwa Mountains of Tanzania. Journal of Zoology, 274/2: 126-133. Accessed February 01, 2013 at http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2007.00363.x/full.

Smit, H., B. Jansen van Vuuren, M. O'Brien, M. Ferguson-Smith, F. Yang, T. Robinson. 2011. Phylogenetic relationships of elephant-shrews (Afrotheria, Macroscelididae). Journal of Zoology, 284/2: 133-143. Accessed February 01, 2013 at http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2011.00790.x/full.

Stanley, W., P. Kihaule, M. Munissi. 2007. Small mammals of two forest reserves in the North Pare Mountains, Tanzania. Journal of East African Natural History, 96/2: 215-226. Accessed February 01, 2013 at http://archive.fieldmuseum.org/tanzania/documents/references/2007_Stanley_etal-North_Pares.pdf.

Tacutu, R., T. Craig, A. Budovsky, D. Wuttke, G. Lehmann, D. Taranukha, J. Costa, V. Fraifeld, J. de Magalhaes. 2013. "Human Ageing Genomic Resources: Integrated Databases and Tools for the Biology and Genetics of Aging" (On-line). AnAge: The Animal Ageing and Longevity Database. Accessed September 24, 2013 at http://genomics.senescence.info/species/.