Amblysomus hottentotus

Geographic Range

Amblysomus hottentotus is the most widely distributed species of golden moles in southern Africa. It is found from the southeastern region of South Africa into Swaziland and southern Mozambique.

• Biogeographic Regions
• ethiopian ethiopian
  • native native

Habitat

The habitat of A. hottentotus is usually the subterranean environment of temperate grasslands with soft soils, but it is also found in coastal forests and savanna woodlands. Amblysomus hottentotus is found from sea level to over 3000 m above sea level and in areas that have a mean rainfall of more than 500 mm. It occupies burrows that can be longer than 200 m and are up to 500 mm deep, with subsurface runs that are only a few centimeters below the surface.

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

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• forest forest
• mountains mountains

Physical Description

Hottentot golden mole weight ranges from 40 to 101 g, with males being larger than females. Males have a head and body length that ranges from 115 to 145 mm and a mean body weight of 80 g., while females have a head and body length that ranges from 120 to 125 mm and a mean body weight of 66 g. Average skull length is 26 mm and the average width is 15.5 mm.

Hottentot golden moles have a cylindrical shape and are covered in fur that varies from reddish to dark brown. The fur grows back toward the hind area and is darker at the tip of the hair than at the base, it has an irridescent sheen. The fur helps to keep these animals dry from moisture in the ground. Underneath this sleek fur is a woolly undercoat that serves as insulation. The fur on the sides and underparts is gray, and the fur color on the cheeks is pale. The tops of the hind feet are covered in hair that is a blackish color.

Hottentot golden mole eyes are covered in skin and they are completely blind. The external ears are not visible and the openings are covered with fur. A smooth, leathery pad covers the nostrils. All of these openings are covered with fur or skin for protection from sand and dirt as A. hottentotus is burrowing. There is no visible tail, but caudal vertebrae are present. The forelimbs are short and powerful and have 4 claws. The third digit is the largest and, along with the second digit, is used for digging. The first and fourth digits are underdeveloped and basically rudimentary. The hind limbs are short and have five digits that are webbed. Compared to moles of the family Talpidae , Amblysomus have limbs that are positioned more medially, which improves digging.

The cranium of A. hottentotus is broad and the premaxilla is narrow. There are 36 teeth, with a dental formula of 3/3, 1/1, 3/3, 2/2. The molars are zalambdodont and there is a well developed posterior talonid on the lower molars.

Male and female A. hottentotus both have a cloaca, which is an opening for the urogenital system. In males, the penis and testes are inside the body.

• Other Physical Features
• endothermic endothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• male larger

Reproduction

Very little is known about the mating systems of A. hottentotus . During courtship males are vocal and make chirrup sounds, they also stamp their feet on the ground. Courtship can be violent because males chase females and force mating. This violence can even lead to the death of females.

Breeding is aseasonal, but fecundity does increase during the rainy season. This occurs because this is the time when food is most abundant and these animals are most active, increasing the possibility of encountering mates. In order to breed, female Hottentot golden moles make a small chamber in their burrows and line it with grass. During the year, a female has several litters, she can even be pregnant while her young are still suckling. Usually 1 to 3 young are born per litter; this small litter size may be related to low predation and high investment per offspring. The young have an average body length of 5 cm, soft claws, and no hair. Females have two pairs of mammae and young suckle until they are 35 to 45 g. When the young reach this weight they are forced out of the burrow.

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

Females care for their young and nurse them in a nest until they reach a size at which they can be independent.

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

Lifespan/Longevity

The lifespan of A. hottentotus is unknown.

Behavior

Hottentot golden moles are fossorial and construct complex burrow systems that contain side tunnels, chambers, and holes that can be used to escape from predators. The leathery nose pad is used to move light soil, while the head and shoulders push mounds of dirt. The front claws dig and move heavier dirt, and the hind feet push mounds of dirt upward to the ground surface. The feet also stamp the bottom of the burrow and the side of the body presses against the sides of the burrow to smooth them. The burrow is extended by 4 to 12 m every day.

Hottentot golden moles are most active at sunrise, sunset, and midnight. Even though they are active for intermittent periods throughout the day, they are most active at night. During the rainy months, when food is more available, activity levels also increase. To save energy, Hottentot golden moles experience daily torpor in which their body temperature falls to within 2 °C of the soil temperature.

As a solitary animal, Hottentot golden moles are territorial and aggressive to conspecifics. They forcefully defend their burrows. In less fertile areas, burrow systems are larger and are defended more aggressively. However, they do co-exist with common mole rats, Cryptomys hottentotus , and may share their burrow systems with members of that species. This is thought to be a symbiotic relationship because the two animals do not compete for food and they use the tunnels of each other's burrows, which reduces the large amount of energy needed to create new burrows.

• Key Behaviors
• fossorial fossorial
• diurnal diurnal
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• daily torpor
• solitary solitary
• territorial territorial

Home Range

No information is available on home ranges.

Communication and Perception

To communicate with others, Hottentot golden moles use vibrations and head knocking to establish their presence and to set burrow boundaries. Their middle ear is modified to improve the detection of low frequency vibrations, which helps these animals while foraging. The head of the malleus, the incus, and the footplate of the stapes are all enlarged. Because the eyes of A. hottentotus are covered with skin, sight is not a sense that it utilizes. Rarely vocal, A. hottentotus chirps when handled and during courtship.

• Communication Channels
• acoustic acoustic

• Other Communication Modes
• vibrations vibrations

• Perception Channels
• tactile tactile
• acoustic acoustic
• vibrations vibrations
• chemical chemical

Food Habits

Hottentot golden moles eat worms, insect larvae, crickets, snails, slugs, and spiders. The moist environment and dew provide them with the amount of water that is needed.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore
  • eats non-insect arthropods
  • vermivore

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

Predation

Mole snakes, genets, mongooses, and jackals are predators of A. hottentotus . With the ability to sense low frequency vibrations, Hottentot golden moles can detect predators and aviod them by escaping to a hole in their complex burrow systems. At night, when Hottentot golden moles might emerge from their burrows, they are exposed to nocturnal predators like barn owls, Tyto alba .

Ecosystem Roles

The ecosystem roles of A. hottentotus are not well known. It is an insectivore, and because A. hottentotus is a highly fossorial species, it is likely involved in soil aeration as a result of digging its complex burrow system.

• Ecosystem Impact
• soil aeration soil aeration

Economic Importance for Humans: Positive

There are no known positive affects of A. hottentotus on humans, aside from their important role in the ecosystem.

Economic Importance for Humans: Negative

There are no known adverse affects of A. hottentotus on humans.

Conservation Status

Hottentot golden moles are an IUCN red list species of least concern. Populations seem to be stable. Like other fossorial mammals, they may be threatened by agricultural development.

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Caitlin Meservey (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.

References

Ciszek, D., P. Myers. 2000. "Chrysochloridae" (On-line). Animal Diversity Wed. Accessed March 20, 2006 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Chrysochloridae.html .

Kuyper, M. 1985. The ecology of the golden mole Amblysomus hottentotus . Mammal Review , 15/1: 3-11.

Mason, M. 2003. Morphology of the middle ear of golden moles (Chrysocholoridae). Journal of Zoology , 260: 391-403.

Mills, G., l. Hess. 1997. The Complete Book of Southern African Mammals . Cape Town, South Africa: Stuik Publishers.

Roberts, A. 1951. Mammals of South Africa . New York, New York: Hafner Publishing Co..

Schoeman, S., N. Bennett, M. van der Merwe, A. Schoeman. 2004. Aseasonal reproduction in the Hottentot golden mole, Amblysomus hottentotus (Afrosoricida: Chrysochloridae) from KwaZulu-Natal, South Africa. African Zoology , 39: 41-46.

Skinner, J., R. Smithers. 1990. The mammals of the southern African subregion . Pretoria, South Africa: University of Pretoria.