- While there is plenty of good news about the effectiveness of protected areas in combating deforestation and related impacts, they “are not a panacea” and “the current reserve system alone may be insufficient to conserve biodiversity in the face of rapidly rising temperatures,” the authors of a study published this month in the journal Diversity and Distributions write.
- The study finds that somewhere between 19 and 67 percent of Amazon protected areas will not have any temperature analogs by the 2050s, depending on the actual rate of warming and the amount of connectivity between protected areas.
- Since many tropical plant and animal species are not likely to be able to tolerate rising temperatures, they will need to shift their ranges and track the movement of “suitable” climates across the Amazon.
Protected areas have emerged as a key conservation tool for curbing deforestation and preserving Earth’s biodiversity. But even they can’t keep out rising global temperatures. So how much will that limit their effectiveness?
According to a 2015 study, at least 36 percent and as much as 57 percent of all Amazonian tree species are likely to qualify as “globally threatened” per International Union for Conservation of Nature (IUCN) Red List criteria by 2050 under an Increased-Governance and Business-As-Usual scenario, respectively.
That would represent a roughly 22 percent increase in the number of threatened plant species around the world, the authors of the study determined. But they also found that effective parks and protected areas can go a long way towards mitigating the threats to biodiversity: if no deforestation occurs in the Amazon’s protected areas, the researchers said, the number of threatened species drops to 29 to 44 percent of all trees.
“This finding reinforces the important message that parks are one of our most powerful tools against deforestation,” the authors of a study published in the journal Diversity and Distributions this month note. “But fences cannot keep out rising temperatures, and even the best-protected areas of the Amazon may be susceptible to the effects of climate change.”
Kenneth Feeley of Florida International University in Miami, the lead author of the Diversity and Distributions study, said that his team’s analysis showed many parks and protected areas of tropical south America contain what can be referred to as “disappearing climates.”
“What this means is that because of global warming, the temperatures or climates found in parks today may not be found in any parks just 50 years from now,” Feeley told Mongabay. “Or if these temperatures do occur in parks in the future, they will be very far from where they are now.”
Since many tropical plant and animal species are not likely to be able to tolerate rising temperatures, they will need to shift their ranges and track the movement of “suitable” climates across the Amazon, Feeley added. “According to our results, these migrating species will have to move from park to park, often crossing through vast swaths of unprotected areas. As such, we should increase efforts not only to expand the system of protected areas but to increase connectivity.”
To get a sense of the best- and worst-case scenarios, Feeley and team examined what would occur if temperatures increase by a range of temperatures, from 1.5-degrees-Celsius to 2.7-degrees-Celsius, and looked for climate analogs within a single protected area, within connected protected areas, or within any protected area in all of tropical South America. They found that somewhere between 19 and 67 percent of Amazon protected areas will not have any temperature analogs by the 2050s, depending on the actual rate of warming and the amount of connectivity between protected areas.
“Under our best case scenario (1.5-degrees-C warming, all parks included in the search for analogs), we actually find that almost all areas (and presumably species) that are currently within parks will have some climate analogs in the future,” Feeley explained. “But this is not really realistic since we cannot expect species to be able to shift their ranges and track suitable climates to anywhere within the continent.”
Under what he called “more realistic scenarios,” in which the team’s search for analogs was limited to just connected parks, the researchers found that about 20 to 35 percent of areas in parks are unlikely to have analogs. According to Feeley, “If we restrict our search for analogs to just within the same parks, then the amount of protected lands that will not have analogs increases to between 45 and 65 percent, depending on the rate of warming.”
The fact that there is such a wide range of possible results shows that there is the possibility for mankind to significantly influence what will happen in the Amazon, Feeley said. If we slow global warming and increase connectivity so that species can track their suitable climates, then many species may able to find refuges in the future. But if we allow business-as-usual and the associated global temperature increases to continue, we risk turning Amazonian parks into isolated islands of forest, and “the vast majority” of protected areas and species will have no place to go to, Feeley added.
It’s worth noting that the study only looked at the effects of rising temperatures, whereas climate change is more complex and includes many variables besides mean annual temperatures that are just as important for the health of forests and the wildlife that rely on them, such as the timing and magnitude of precipitation. “If we include more climate variables or if we consider the effects of other disturbances, such as habitat degradation and fires, then the existence and availability of ‘suitable’ climates for Amazonian species will invariably decrease even more,” Feeley said.
So while there is plenty of good news about the effectiveness of protected areas in combating deforestation and related impacts, they “are not a panacea” and “the current reserve system alone may be insufficient to conserve biodiversity in the face of rapidly rising temperatures,” Feeley and his co-author write.
“Migration, whether through explicit corridors or through landscapes of working forests managed to facilitate species movement, will be paramount in determining the future of Amazonia. In the absence of species migrations, disappearing climates will translate into many more disappearing species than would occur from deforestation alone.”
- Feeley, K. J., & Silman, M. R. (2016). Disappearing climates will limit the efficacy of Amazonian protected areas. Diversity and Distributions. doi:10.1111/ddi.12475
- Ter Steege, H., Pitman, N. C., Killeen, T. J., Laurance, W. F., Peres, C. A., Guevara, J. E., … & de Souza Coelho, L. (2015). Estimating the global conservation status of more than 15,000 Amazonian tree species. Science advances, 1(10), e1500936. doi:10.1126/sciadv.1500936