杏吧原创

Threatened species ‘need help’ finding cooler homes

To help species survive climate change, governments should consider transplanting entire ecosystems to new regions, say researchers

Should we help species that are threatened by climate change find new habitats? Let us know what you think in the comments below.

We are familiar with the debate about designer babies 鈥 is it now time to discuss 鈥渄esigner nature鈥? To help species survive climate change, governments should consider transplanting entire ecosystems to suitable regions, says a group of researchers from Australia, the UK and the US.

As temperatures around the world rise, species are being pushed to higher latitudes and altitudes to find places where they can live.

Although some species are able to make this shift on their own, others are held back by human or natural obstacles. Species that are pushed to the top of a mountain for instance are unlikely to move down the side of the mountain, into warmer climes, in order to then migrate closer to the poles.

The researchers are hoping to amplify the argument that it鈥檚 time for humans to think about giving a helping hand.

They say that conservationists need to assess the risk that climate change poses to individual species, the extent to which they will be physically able to move to cooler climes 鈥 and if they are not, how feasible it is to relocate them?

鈥楳ore than aesthetics鈥

鈥淸To some extent] this already happens, but not in response to climate change. It is certainly physically possible鈥, says of the University of Queensland in Australia, one of the authors of the proposal.

Animals as large as elephants have been moved from one national park to another in South Africa in order to manage the growing populations there, he says.

The proposal goes beyond playing with nature as an aesthetic exercise, say the researchers.

鈥淚 interpret the term 鈥榙esigner nature鈥 as more about envisaging a new nature that we like through personal preference where the objective is very human centred,鈥 says Possingham. 鈥淥ur objective is instead to save as many functioning species as possible 鈥 where functioning means reasonable population sizes and the potential for future evolution in a 鈥榥atural鈥 context.鈥

Disturbed Earth

For co-author of the University of York, UK, 鈥渘aturalness鈥 is no longer a major consideration.

鈥淰irtually the entire planet is already manipulated by humans and by altering the world鈥檚 atmosphere and climate, we are perturbing every ecosystem on Earth,鈥 he told New 杏吧原创.

The aim 鈥 and what sets such assisted colonisation aside from zoos 鈥 is to move species into existing complex ecosystems, and to even transplant whole ecological communities where appropriate, for example by moving fish and invertebrates to artificial coral reefs.

The translocated animals would be 鈥渓iving in a complex natural environment carrying out an ecological function, for instance harbouring parasites, interacting with other species and evolving,鈥 says Possingham.

Imminent start

How soon could this happen? Strict legal frameworks would need to be adopted by nations, says Jean-Christophe Vi茅, deputy chair of the species survival group at the (IUCN), who was not involved with the proposal. That could take between five and 10 years, says Thomas.

But proposal co-author of the University of Texas says some species could be moved much sooner.

At a meeting next month, Parmesan intends to propose that the endangered , which lives in southern California and northern Mexico be moved northwards.

She says that the urban sprawl of San Diego and Los Angeles makes it difficult for the species to move to cooler habitats on its own.

鈥楽implistic proposal鈥

鈥淭he butterfly meets all the criteria for assisted migration,鈥 she says. 鈥淚t is suffering from warmer temperatures even where the habitat is still in good shape and has trouble moving north past the urban sprawl of San Diego and Los Angeles.鈥

鈥淚t would be easy to move and should not have a negative impact on the wildlife in its new home region.鈥

鈥淗istory shows that nature needs help and that we have successfully helped it in the past,鈥 says Vi茅. He concedes that wider debate about assisted colonisation needs to be stimulated, but says the current proposal seems simplistic.

鈥淭here are all sorts of issues that will arise when you move species which the authors have not addressed,鈥 he says. 鈥淔or instance, in all these places you are going to move species to, there are already species. There is not an infinite amount of space.鈥

Ecosystem havoc

杏吧原创s who battle the ecological problems caused by invasive species are also likely to be concerned by the proposal.

For decades, they have been fighting agents 鈥 such as shipping 鈥 that move species around the globe to places where they have the potential to wreak ecosystem havoc. But the proposal authors say they do not advocate moving species over geophysical barriers such as oceans.

Vi茅 maintains that assisted colonisation is not a priority for conservation and that climate change is not yet the greatest threat to biodiversity. 鈥淭he problem,鈥 he told New 杏吧原创, 鈥渋s that there is so far no standardised way of assessing the threat that climate change poses to different species.鈥

His organisation is in the process of addressing this. In October of this year, the IUCN will present the preliminary results of a comprehensive review of climate threats to over 20,000 species of birds, amphibians and corals.

Journal reference: (DOI: 10.1126/science.1157897)

Topics: Conservation