MISSOULA – While the world continues to grapple with measures to slow climate change, University of Montana conservation researcher Jedediah Brodie has been more focused lately on what additional measures are needed to stem the tide of extinctions.
Brodie is the lead author of an article recently published in Science magazine calling for the establishment of an international policy to set guidelines for species conservation and climate change adaption through assisted colonization – moving climate-vulnerable species into new areas to avoid the deterioration of climatic conditions in their historical ranges.
According to research, one-third of species may now have an increased risk of extinction from climate change. In response, Brodie and fellow authors suggest that many organisms that can’t adapt will “either need to move poleward in latitude, upward in elevation, downward in water depth, or to refugial areas that might lie outside their current or historical indigenous ranges.”
A big idea for a big problem, to be sure, but one that is not insurmountable, Brodie said.
“Humans have been moving species around all over the globe for millennia, and we've got well-established protocols for doing this for conservation purposes,” Brodie said. “What makes assisted colonization more difficult than other conservation translocations is that you're moving a species into an area where it hasn't naturally occurred for a long time or ever.”
Even so, Brodie said, these logistical hurdles promise to be easier to summit than the political ones, which is at the heart and purpose of the Science article. In it, the researchers urge the governing body of the UN’s Convention on Biological Diversity – which meets later this year in China – to empower a technical committee to evaluate and regulate assisted colonization. The CBD treaty, ratified by 196 nations, encourages actions leading to a sustainable future.
Assisted colonization has long been discussed by scientists but rarely deployed. One instance cited by Brodie is an ongoing effort by a private group to save, through assisted colonization, an endangered conifer tree, Torreya taxifolia, whose native range is a small section along the eastern bluffs of the Apalachicola River in the Florida panhandle.
These often-scattershot efforts frequently lack guidance and oversight, the authors note, and run the real risk of unintended consequences such as the establishment of invasive species.
“The most important thing to do is vetting beforehand,” Brodie said. “It’s actually very difficult to predict which species might become invasive in particular areas, but there are risk-assessment protocols and tools for making decisions in the face of substantial uncertainty.”
More certain will be the need for programs on a scale large enough to assist species in migrating across international boundaries and around infrastructure, such as roads and bridges, and other disturbances, both human created and natural.
“Some of the most at-risk ecosystems are oceanic islands, particularly those that are relatively low in elevation,” Brodie said. “Species in these areas have nowhere to go if climatic conditions become unsuitable. And islands hold a significant portion of global biodiversity.”
Although the Science article focuses primarily on assisted colonization, the authors also address the possibility of moving genetic material, through gene editing, from one species to another to promote greater resilience to warming environments. They note that such “assisted evolution” is already being considered for a variety of species, including corals and trees, while also acknowledging that this avenue raises complicated questions about species identification and the limits of intervention taken in the name of conservation.
Brodie calls the idea “both intriguing and scary” and points to the need for careful planning on an international scale.
Of course Montana wildlife is not immune to the negative impacts of global warming. Brodie points to the diminutive pika as one species that could one day be a candidate for assisted colonization.
“They’re alpine dwellers and local populations can be driven extinct if summers get too hot or there isn't enough winter snowpack,” he said.
In whatever form assisted colonization takes, the authors write that the time is now to shape its ultimate implementation.
“Ideas for action consistently run ahead of policy to guide responsible action,” said Mark Schwartz of the University of California at Davis, a co-author of the study. “As we embrace managing biodiversity on a radically changing planet, now is the time for global governance on how to responsibly engage in assisted colonization, including when not to deploy such actions.”
Adds Brodie, “The path to success is through the CBD. The upcoming conference in China is the best opportunity to get the ball rolling.”
What the other co-authors are saying about assisted colonization:
Dr. Susan Lieberman, vice president for International Policy, Wildlife Conservation Society: “Many governments have not yet established regulations or policy frameworks around assisted colonization but the need for such efforts is increasingly urgent. The accelerating rates of the climate and biodiversity emergencies necessitate engagement from many stakeholders and sectors of society. International leadership through the CBD that brings together experts can provide a model for national policies.”
Axel Moehrenschlager of the International Union for Conservation of Nature Conservation Translocation Specialist Group and Calgary Zoo: “Increasingly life and death decisions need to be made to help save species. Assisted colonization is a powerful conservation translocation tool that can help prevent extinction of plants and animals in all ecosystems on Earth. Like many innovations, it needs to be employed thoughtfully to maximize profound benefits for nature and humanity.”
Philip J. Seddon of the University of Otago: “Rapid environmental change is challenging traditional conservation management approaches, such as ecosystem restoration to some arbitrary past target state. We need to recognize that historically suitable sites for some species have or will become unable to support viable populations in the near future, and the barriers to natural dispersal, many of which humans have created, will trap some species and doom them to extinction unless we intervene. We need to be able to assist such stranded species to access suitable areas of habitat, wherever these lie.”
Said James Watson of the University of Queensland: “The status quo in how we do conservation will not work – regardless of the level of ambition outlined in climate change and biodiversity agenda – for many species around the world. Climate change, alongside death and taxes, are the only true certainties we face, and nations around the world now need guidance in how best to deal with helping species survive the current climate crisis.”
Said Jon Paul Rodríguez of IUCN Species Survival Commission: “A desired outcome of all the work that we do is the implementation of evidence-based conservation interventions by policy makers and governments. It requires that scientific research be repackaged for multiple audiences, synthesized and adapted to local contexts. Creating international guidelines that reflect the consensus of academics, practitioners, communicators and local communities, for example, is an important gap that must be addressed.”
Contact: Jedediah Brodie, UM associate professor and John Craighead Chair of Conservation, 406-243-5528, email@example.com.