Marine alien species have not been as well studied in South Africa as their terrestrial counterparts. However, recent research by C·I·B researchers has shed some light on the occurrence of marine alien species in Western Cape harbours.
The volcanic island of La Réunion in the Indian Ocean is the least disrupted of the biodiversity-rich islands of the Mascarene archipelago, with around 30% of the native vegetation still intact. She-oak or ironwood (Casuarina equisetifolia), a fast-growing tree native to Australia, Melanesia, Micronesia, the Philippines, Polynesia, and Southeast Asia, was introduced to La Réunion in 1738, mainly for use as firewood.
All alien species cause changes to the ecosystems to which they are introduced. Such impacts are of many types - some are dramatic and obvious and can easily be classified as desirable or undesirable. However, for the vast majority of alien species, no information on impact is available. This greatly complicates the task of objectively assigning priority to management.
Eradication of invasive alien plants requires that all populations of the plants have been found and every plant removed. This entails intensive searching, which often comes at a great expense. Maps that show where species are likely to occur are useful for guiding searches, and may reduce the costs and increase the success of eradication operations. Such maps are based on models that explore the links between plant distributions and climatic factors in order to predict where the plants might occur.
Recently published C·I·B research conducted in association with the International Polar Year ‘Aliens in Antarctica’ project has measured the propagule load carried in the clothing and gear of researchers and visitors to the Antarctic region.