By Gabriel Tamaska
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).
Habitat
(5904 ft)
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).
These animals are found in the following types of habitat:
freshwater
.
Terrestrial Biomes:
rainforest
.
Aquatic Biomes:
rivers and streams.
Wetlands: swamp
.
Physical Description
(10.56 to 33.44 oz; avg. 22 oz)
(21.06 to 25.2 in; avg. 23.13 in)
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).
Some key physical features:
endothermic
; bilateral symmetry
.
Reproduction
Wet season
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
; gonochoric/gonochoristic/dioecious (sexes separate); sexual
; fertilization
(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).
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
(eats terrestrial vertebrates, piscivore
, insectivore
, eats non-insect arthropods, molluscivore
).
Animal Foods:
amphibians; fish; insects; terrestrial non-insect arthropods; mollusks.
Conservation Status
IUCN Red List: [link]:
Least Concern.
US Migratory Bird Act: [link]:
No special status.
US Federal List: [link]:
No special status.
CITES: [link]:
No special 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.
For More Information
Find Potamogale velox information at
Contributors
Gabriel Tamaska (author), University of Michigan.
Ondrej Podlaha (editor), University of Michigan.

