Invasive plants to devastate annual wildebeest migration
According to new research, scientists have found that a number of invasive alien plant species initially introduced as ornamental plants at tourism facilities are now spreading rapidly throughout the Serengeti-Mara ecosystem, posing a major threat to wildlife, including the annual wildebeest and zebra migration as well as a range of other plant and animal species.
Action on Invasives
The global cost of invasive species is estimated at US$1.4 trillion per year – close to 5% of global gross domestic product. Invasives disproportionately affect vulnerable communities in poor rural areas, especially in developing countries which depend on natural resources, healthy ecosystems, trade and tourism for their livelihoods.
Biological control of hawkweeds
European hawkweeds are invasive in North American pastures, where mechanical methods of control are difficult and ineffective. Chemical control with broad-spectrum herbicides is not selective and relatively expensive, with the weed often recolonising untreated pastures. Insects that feed on hawkweeds in Europe have been studied as potential biological control agents for North America since 2000. Two agents have been released in North America – the gall wasp, Aulacidea subterminalis, and the hoverfly, Cheilosia urban.