Recent studies suggest the rise in invasive species stems from international trade. Global warming has also contributed to species migration and survival in the wild. The Spanish authorities have drawn up a list of 168 offending species including the raccoon and mink, zebra mussels, and one of the worse offenders the ruddy duck.
In New Zealand rats are driving the yellowhead bird to extinction and the chrytrid fungi is causing a worldwide decline in amphibians but can species really recover after competition is successfully eradicated? It seems that in some cases they can. The near extinct black vented shearwater is recovering on a Mexican island after the eradication of cats, goats and sheep. The wallaby is also recovering after red fox were taken out in Australia.
However, there are also a growing number of scientists who argue that to eradicate invasives is costly, cruel and ultimately unnecessary. In Puerto Rico invasive species have been the only plant and wildlife able to survive in eroded soils. Their encroachment has returned lifeless areas to thriving jungles, eventually providing a more encouraging environment for native species to return.
If we can’t beat them then it may even be time to learn from these ecological survivors.
Producer Helen Lennard
Repeated on 31:03:2011 13:31:00.