It is time to drop the alien versus native species dichotomy in conservation, according to a group of eminent scientists concerned with the restoration of ecosystems around the world.
In an opinion piece published today in Nature, Australian Laureate Fellow Winthrop Professor Richard Hobbs at The University of Western Australia and his co-authors argue that it is counterproductive to vilify non-native species if they do not harm the environment.
“Claims that introduced species pose an apocalyptic threat to biodiversity are not backed by data,” they claim. “Most human and natural communities now consist both of long-term residents and of new arrivals, and ecosystems are emerging that never existed before.
“It is impractical to try to restore ecosystems to some ‘rightful' historical state. We must embrace the fact of ‘novel ecosystems' and incorporate many alien species into management plans, rather than try to achieve the often impossible goal of eradicating them.”
Professor Hobbs said he and his colleagues were not suggesting that conservationists abandon their efforts to mitigate serious problems caused by some introduced species – such as cane toads and foxes in Australia – or that governments should stop trying to prevent potentially harmful dangerous species from entering their countries.
“But we urge conservationists and land managers to organise priorities around whether species are producing benefits or harm to biodiversity, human health, ecological services and economies,” they write.
“Nearly two centuries on from the introduction of the concept of nativeness, it is time for conservationists to focus much more on the functions of species, and much less on where they originated.”
The researchers cite the example of non-native honeysuckles in Pennsylvania, which attract more native bird species, and tamarisks introduced to some of the USA's southern states which are the preferred nesting habitat of the endangered south western willow flycatcher.