By Sophie Simon
“Climate change” has been a major buzzword in recent public discourse, thrown around by seemingly everyone from the media to politicians, environmental activists to concerned citizens. In the slew of ostensibly disastrous effects both proclaimed and denied by the public–from rising seas to disease outbreak–there is one very real, but oft-overlooked victim of climate change: the biodiversity of our planet.
As the Earth progressively warms with climate change, species that are not able to adapt to shifting temperatures will be propelled towards extinction. Yet according to a new study by the International Union for Conservation of Nature (IUCN) published in research journal Plos One, the majority of species that are most vulnerable to climate change are not given conservation priority.
This large-scale study pioneered new methods to assess the vulnerability of species to climate change and the geographic areas where these species are concentrated. Drawing on the work of more than 100 scientists, the study assessed the entirety of the world’s birds, amphibians, and corals–a total of 16,857 species.
Previous approaches to quantify the impacts of climate change on biodiversity focused singularly on species’ exposure, largely ignoring the biological differences that affect vulnerability. In the IUCN assessment, however, each species was profiled for its exposure to climate change, along with its sensitivity and adaptability to changes in natural habitat. Based on their unique biological and ecological characteristics, different species were found to have varying degrees of tolerance to alterations in their surroundings.
Researchers with the IUCN found striking statistics: up to 83% of birds, 66% of amphibians, and 70% of corals that they identified as “highly vulnerable to climate change” are not on the IUCN Red List of Threatened Species. The Red List is the most comprehensive and widely-recognized inventory of the conservation status of the Earth’s biological species. It provides precise criteria for the extinction risk for thousands of species and subspecies of all regions of the world.
A species makes the list if it has been threatened, as determined by leading species scientists through a peer review process. Experts identify threats to species, including: invasive species, pollution, natural disasters, disease, human disturbances like deforestation and mining, over-exploitation of resources, hunting, and habitat loss/degradation from agriculture. Threatened species are then classified as “vulnerable”, “endangered”, or “critically endangered”.
Why is this single list so important? It is more than a catalogue of species. The list is intended to inform species-based conservation actions, influence conservation decision-making, and monitor current status and extinction risk trends in species. The Red List is not only a conservation canon, but meant to bring about direct action.
For example, the Siberian or Amur Tiger has been listed as critically endangered by the IUCN Red List due to relentless hunting and habitat loss, primarily in the form of logging and development in Russia’s birch forests. In the 1930’s, the tiger population had dropped as low as 20-30 animals, yet thanks to conservation efforts, may be as high as 360 individuals today. The identification of the Amur Tiger as a critically endangered species has led to its protection; now the IUCN deems its population trend as “stable.”
Recognition by the Red List, a reference for international and regional wildlife conservation groups, has been vital to the survival of species like the Amur Tiger. That many vulnerable species would not be recognized by this established ecological benchmark is a high source of concern.
According to the 2013 IUCN study, highly climate-vulnerable species not yet identified by the Red List are unlikely to be receiving necessary conservation attention. “The findings revealed some alarming surprises,” stated study leader Wendy Foden, of the IUCN Global Species Programme. “We hadn’t expected that so many species and areas that were not previously considered to be of concern would emerge as highly vulnerable to climate change. Clearly, if we simply carry on with conservation as usual, without taking climate change into account, we’ll fail to help many of the species and areas that need it most.”
Furthermore, the study identified geographic areas where the species with greatest relative vulnerability to climate change are concentrated. Vulnerability hotspots included the Amazon basin for birds and amphibians, and the central Indo-west Pacific for corals.
Unsurprisingly, a significant portion of these species at risk from climate change are already threatened with extinction. Not only are such species in critical need of climate-based conservation, but also endangered by ecological disruption through means like habitat loss, overexploitation, and invasive alien species. The study found that up to 9% of birds, 15% of amphibians, and 9% of corals are both highly vulnerable to the changing climate and already considered endangered.
While these currently endangered species are already given conservation attention, the remaining highly climate change vulnerable (but not currently threatened) species require newly directed priority. Areas of greatest concentration for these species include: the Amazon basin and eastern South America, Europe, the Congo basin, parts of North America, northern and central Asia, and Australia for birds; the Amazon basin, Eurasia, southern North America to Mesoamerica and Madagascar for amphibians; the Caribbean and southern Red Sea for corals.
In all, the study’s findings suggest that species and regions that need to be highlighted are not necessarily those with greatest exposure to climate change, but those at risk with both high sensitivity and low adaptive capacity. Vulnerability cannot be determined by climate alone; there is case-by-case variability with each species. This IUCN study presents both scientists and conservationists with invaluable data on individual species of birds, amphibians, and corals.
Factors that affect the well-being of the world’s species are multi-faceted and ever-changing; preservation perspectives must always be evolving to adjust with changing environments. Scientific findings by researchers can help direct perpetual tinkering with conservation criteria and considerations. It is therefore essential that the Red List be reflective of the most up-to-date information on species threats, as it is the most prominent tool in determining conservation efforts today.
Heeding the results of the most recent IUCN study, current conservation efforts should be refocused to also include individual species that are highly vulnerable in light of the Earth’s changing climate. IUCN researchers suggest the findings be used to “devise species and area-specific conservation interventions and indices.” If not, climate change threatens to more rapidly increase extinction rates and irrevocably diminish the biodiversity of our diversely populated planet.
Sophie Simon is an Intern at the Earth Institute Center for Environmental Sustainability. She is studying Geography and Human Rights at Macaulay Honors College at Hunter College.
Climate is an important environmental influence on ecosystems. Climate changes and the impacts of climate change affect ecosystems in a variety of ways. For instance, warming could force species to migrate to higher latitudes or higher elevations where temperatures are more conducive to their survival. Similarly, as sea level rises, saltwater intrusion into a freshwater system may force some key species to relocate or die, thus removing predators or prey that were critical in the existing food chain.