Mad Mammal Monday: the otters of Africa 

The focus of today's Mad Mammal Monday: African OTTERS! The MammalMAP facebook group's news feed has so far touched on the Cape Clawless Otter Aonyx capensis – also called the African Clawless Otter. It is IUCN "Least Concern" – this is the species in the photos shown here. There are also two other kinds of otters in Africa: the Congo Clawless Otter Aonyx congicus – IUCN Red List Category is Data Deficient, and the Spotted-Necked Otter Lutra maculicollis – IUCN Red List Category is Lower Concern.

The DNA jury is still out on whether the Congo Clawless Otter is a distinct species, or just a regional variation of the African Clawless Otter. In any event, they are very similar to one another. As their names suggest, they are clawless, and only occasionally are the possibly-vestigial grooming claws spotted on their hind limbs. Their unwebbed digits give them the sensitivity and dexterity they need to catch prey with their hands. Meals of choice are crustaceans and large fish, and they have heavily-muscled necks and large teeth that enable them to crush these bony prey.

Like the other African otters, Spotted-Necked Otters rely on their water-resistant coats, rather than layers of fat, for warmth. But in many other respects, Spotted-Necked Otters are quite similar to the Eurasian and Hairy-Nosed Otters of Europe and Asia. They have well-developed claws and small teeth that are better suited to catching fish than crushing crustaceans. They are also more aquatic than the other African otters, and have fully webbed paws.

Otters occur throughout sub-Saharan Africa, everywhere where there is water. Although the African otters are classified with different levels of risk, ongoing land drainage, increasing water pollution, food competition (caused by the introduction of exotic species like Nile Perch) and direct persecution as competitors for fish are all cross-continental factors that may compromise their survival risks in coming years. To counter these threats, the IUCN has called for increasing awareness about otters, and has highlighted that we need to know more about them, and need to keep better tabs on them.

That's where you all come in! Please submit any African otter records you have (photographs with date and location details) to the virtual mammal museum vmus.adu.org.za and help us to compile an encyclopaedia of otter information. We'll store these records in this online museum, and will make sure that they land up in the hands of people who are making it their business to monitor, manage and conserve these awesome aquatic animals.

Tali Hoffman
2012-08-20

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