Potamogale velox

Geographic Range

Potamogale velox is found only in central Africa, from the southern regions of Nigeria, Gabon, and The Central African Republic to the Northern regions of Angolia and Zambia. It is rarely found west of Tanzania and Uganda. One small population lives between Uganda and Kenya (African Mammal Databank).

• Biogeographic Regions
• ethiopian ethiopian
  • native native

Habitat

P. velox prefers aquatic environments in the central African rain forest. Its preferred habitats include both high and low order streams, swamps, and during the rainy season some animals may migrate to small forest pools (Kingdon, 1997; Walker 1983).

• Habitat Regions
• freshwater freshwater

• Terrestrial Biomes
• rainforest rainforest

• Aquatic Biomes
• rivers and streams

• Wetlands
• swamp swamp

Physical Description

The Giant Otter Shrew got its common name because of its physical resemblance to otters. It has a broad, flat muzzle covered with stiff whiskers, and flaps of skin that seal its nostrils when diving. It has small eyes and external ears. The thick round body is covered with a dense undercoat and course guard hairs. P. velox has a dark brown back and whitish under parts. The tail is covered with a short, silky coat of fur. It is compressed laterally, and allows P. velox to swim with a fish-like motion (Knigdon, 1997; Nicoll, 1985; Walker, 1983). Legs, which are short and lack webbed digits, are not used for swimming. The hind feet have a flap if skin along the inside that allows them to be held snugly against the body when swimming. There are also two syndactylous toes on the hind feet, used for grooming. On land P. velox is plantigrade (Walker, 1983; Nicoll, 1985). Females have two mammae on the lower abdomen (Nicoll, 1985).

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

Reproduction

Males move long distances in search of mates and it is thought that males rut during the wet season (Nicoll, 1985).

Little is known about the reproductive patterns of P. velox , but females examined were generally developing twins (Nicoll, 1985).

• Key Reproductive Features
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
  • internal internal

Lifespan/Longevity

Little in known about the longevity of P. velox , but when held in captivity individuals quickly deteriorate (Nicoll, 1985).

Behavior

P. velox is a strong, agile swimmer. Activity starts at dusk and continues into the night. P. velox digs burrows in the stream bank with underwater entrances and shelters there during the day. It chooses dry leaves with which to line its nest. This is also where breeding takes place. The burrows are frequently changed. When foraging, otter shrews take frequent grooming breaks. When traveling upstream the otter shrew travels on the bank more frequently than when traveling downstream. The night foraging routine is regular and predictable, and covers up to 800 meters a night. P. velox regularly visited discrete piles of feces that were sheltered and above the stream flood line (Nicoll, 1985).

• Key Behaviors
• nocturnal nocturnal
• motile motile
• solitary solitary

Communication and Perception

• Perception Channels
• tactile tactile
• chemical chemical

Food Habits

P. velox is a nocturnal predator, hunting primarily by touch and scent in calm pools. It searches both the pool and the bank for food. It prefers areas that have cover to retreat to when it feels threatened (Nicoll, 1985). P. velox attacks prey using sharp bites, sometimes pinning the prey with its fore feet, and flipping crabs over to attack their ventral surface. When attacking larger prey P. velox hisses, and avoids crabs larger than 7 cm across (Nicoll, 1985; Walker, 1983). The prey preference varies among individuals; some prefer crabs; others, frogs, or even fish. Frogs are eaten headfirst and fish are pulled into manageable bits. Prey is consumed on the bank (Nicoll, 1985). They also eat insects, mollusks, and prawns.

• Primary Diet
• carnivore carnivore
  • eats terrestrial vertebrates
  • piscivore piscivore
  • insectivore insectivore
  • eats non-insect arthropods
  • molluscivore molluscivore

• Animal Foods
• amphibians
• fish
• insects
• terrestrial non-insect arthropods
• mollusks

Conservation Status

The habitat of P. velox is highly fragmented (Walker, 1983; African Mammal Databank; Nicoll, 1985). While they can tolerate seasonally cloudy streams, streams muddied from erosion and deforestation are little used (Walker, 1983; African Mammal Databank). Habitat quality is apparently important to this species. Some drown in fishing nets or fish traps (Walker, 1983; Kingdon, 1997), and members of this species have not survived well in captivity (Nicoll, 1985). There is ongoing research about the effects of human activity on them (African Mammal Databank).

Other Comments

Information on P. velox is scarce, and much of it is in languages other than English.

Despite it's common name "shrew" it should be noted that P. velox is a tenrec, not a shrew.

Additional Links

Encyclopedia of Life

Contributors

Gabriel Tamaska (author), University of Michigan-Ann Arbor, Ondrej Podlaha (editor), University of Michigan-Ann Arbor.

References

Kingdon, J. 1997. Giant otter shrew. Pp. 137 in The Kingdon field guide to African Mammals . London and New York: Natural World: Academic Press.

Nicoll, M. 1985. The biology of the giant otter shrew *Potamogale velox*. National Geographic Society Research Reports , 21: 331-337.

Walker, E., F. Warnic, S. Hamlet, K. Lange, M. Davis. 1983. Giant African Water or Otter Shrew. Pp. 112 in Mammals of the World . Baltimore, Maryland: Johns Hopkins University Press.

"African Mammals Databank (*Potamogale Velox*)" (On-line). Accessed October 5, 2001 at http://www.gisbau.uniroma1.it/amd/amd028b.html .