"As soon as I started to see what an impact climate change was having on wild species and documenting wild species going extinct," Parmesan says, she began to think about how the species might be saved. Short of the world's governments paying heed and cutting greenhouse gas emissions sharply to enable Earth to cool down, she and a few others began pondering alternative actions in particular, human assistance. She sees assisted migration, as the concept has come to be called, as the only hope to save at least some species though certainly only a small minority of those in peril. Jessica J. Hellmann, a conservation biologist at the University of Notre Dame, believes that most assisted migrations will require an advocate who favors a particular species for sentimental or, especially, economic reasons. (Parmesan understandably has several western butterfly species in mind.) Timber companies are already taking climate change into account when planting new trees to be harvested decades hence.
One amateur group, the Torreya Guardians, are attempting to "rewild" the endangered Florida torreya, a conifer tree. Native only to a 65-kilometer length of the Apalachicola River, it began to decline in the 1950s, probably because of fungal pathogens, and is thought to be "left behind" in a habitat hole that has prevented its migration northward. A few dozen seedlings were planted on private land near Waynesville, N.C., last July, with more expected.
Such assisted migration, Parmesan acknowledges, horrifies some conservation biologists: "They spend a good bit of time working against invasive species, and one big cause of species being endangered is being outcompeted by invasive species." In the particular case of the Torreya Guardians, "many biologists are queasy about it because they feel they didn't do the groundwork to see how it would impact the [new] community," she says. So she advocates systematic studies of threatened species' habitats where they thrive and why and what might threaten them.
Better theoretical tools will certainly help. Today's efforts, called climate envelope models, simply consider the temperature, precipitation levels and soil types that a species prefers, then feed that into a standard climate model to predict where a species might naturally migrate, sans human obstacles and assistance. Hellmann is working on a model that incorporates biological elements, such as genetics and competition among species what other species might be attracted or at risk, evolutionary responses, and so on because populations often vary genetically across a species' range. With such data, Hellmann remarks, "we can perhaps get rules of thumb that can help set population priorities."
Assisted migration is a more active idea in academia than among traditional conservation organizations. For example, the Nature Conservancy is studying the idea. "Assisted migration is a relatively drastic option," says Patrick Gonzalez, a climate change expert at the organization, "but might come about if all of our other options fail and a species is in danger of extinction. But it entails a lot of risks."
Such caution frustrates Parmesan, who was a co-author on a 2008 paper in Science proposing a "decision framework" for assessing the possible relocation of endangered species. "If we do nothing, we're also risking biodiversity. Conservation managers have the attitude that doing nothing is good, and my approach is that doing nothing is bad," she explains.
But she is more dismayed by policy makers. In its last months in office, the Bush administration altered the Endangered Species Act to explicitly exclude climate change from factors that would necessitate independent, multiagency studies of species proposed to be protected. Parmesan's reaction was, she says, "mostly unprintable. It's in defiance of what every conservation organization is moving toward." John Kostyak of the National Wildlife Federation says that "chances are very good" for the Obama administration to reverse the regulation, although it could take as long as a year.
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Add Commentis "assisted migration" really a good idea? if creatures are supposed to adapt to the changing environment then wouldn't assisted migration run counter to natural evolution? shouldn't creatures be allowed to evolved in face of the changing environment? and wouldn't that create creatures able to survive in that environment?
Reply | Report Abuse | Link to thisUnfortunately, changes are occuring too rapidly for natural response to keep up. I agree that the idea of assisted migration presents its own set of problems. Very likely the species being relocated will need to be held in cotrolled habitats until their introduction to the wilds of another region.
Reply | Report Abuse | Link to thisTo be honest I don't have much faith that the idea will be effective. Our ecosystem's regions have each developed a startling array of interwoven lifeforms which are so specialized and dependent on one another that to pick one and move it to another system, even of similar climate and terrain conditions, can (in my opinion) be viewed as little more than a short stay of execution.
Each species lives in a web of interactions. For a butterfly to be displaced, you have to displace the plants it depends on too. Also to keep it in check you must also displace its predators and the other species the whole system depend on. (Ecology is the science of system interactions). So climate change means we will have to ensure the displacement of whole sytems, even if they do evolve somewhat. Better to fight against climate change!
Reply | Report Abuse | Link to thisI thought that too, but I think the concern is that the change is happening at a pace that most species can't evolve fast enough to adapt to. Rapid climate changes such as this just wipe everything out. In this case, even if you wanted to be completely anthropocentric, you'd have to realize that in a mass extinction, seven billion people will quickly run out of food.
Reply | Report Abuse | Link to thisI thought that too, but I think the concern is that the change is happening at a pace that most species can't evolve fast enough to adapt to. Rapid climate changes such as this just wipe everything out. In this case, even if you wanted to be completely anthropocentric, you'd have to realize that in a mass extinction, seven billion people will quickly run out of food.
Reply | Report Abuse | Link to thisI thought that too, but I think the concern is that the change is happening at a pace that most species can't evolve fast enough to adapt to. Rapid climate changes such as this just wipe everything out. In this case, even if you wanted to be completely anthropocentric, you'd have to realize that in a mass extinction, seven billion people will quickly run out of food.
Reply | Report Abuse | Link to thisAssisted Migration? Sounds Biblical to me. Noah tried it, almost got it right except for those damned mosquitoes.
Reply | Report Abuse | Link to thisI wonder, if you took two of every species on earth, and took their average masses, how big of a ship you'd need to hold them all. ...not to mention enough food to keep them alive for 40 days, + however many days it took to grow more food once the flood receded and plants started growing again. And then there's the carnivores. How many mice would you have to actually bring to feed the snakes, and how many snakes would you need to bring to feed the owls and...
Reply | Report Abuse | Link to thisThat'd be a fun problem to work out.
With or without planning, assisted migration is occurring. One may see this in the transfer of unwashed heavy equipment from work site to work site, international trade, the movement of flora and fauna in the pet and landscaping industries.
Reply | Report Abuse | Link to thisPerhaps if we do this intentionally and rationally, something good will result. But, as I said, it is occurring and will continue to occur whatever our views on the subject.
It is tantalizingly simple to state but notoriously difficult to solve.
Reply | Report Abuse | Link to thisit says nothing about global warming wow
Reply | Report Abuse | Link to thisthis says nothing about migration wow wont come here when i have homework
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