Unlike for their botanical counterparts, little has been published about the invasion of alien animals into South Africa's ecosystems.

Now Assoc Prof Mike Picker of UCT's Department of Zoology has, with colleague Assoc Prof Charles Griffiths, penned what they say is the first book on the alien animals of Africa.

Alien and Invasive Animals: A South African perspective, published by Struik Nature, puts the number of such creatures - land, sea and fresh water - at about 600 species. (Although the authors concede that this number is probably an underestimate.) In the book, Griffiths and Picker pool their vast research resources to describe 270 alien animal species in detail, the history of their invasion (deliberate or otherwise), and the ecological and economic impacts they have on the country.