by Samantha Thompson
Scientists are searching for ways to avoid losing biodiversity to global warming. One way is by enhancing species resilience to environmental change. Resilience is the ability of an ecosystem or species to maintain key functions and processes in the face of stresses or pressures, either by resisting and/or adapting to change. Fuentes explored the resilience of 58 marine regional turtle management units (RMUs) to climate change, including all species of marine turtles worldwide. Using expert opinions from 33 different IUCN-SSC Marine Turtle Specialist Group respondents, the researchers were able to develop a Resilience Index. This was used in order to consider qualitative characteristics of RMUs such as population size, rookery vulnerability, and genetic diversity, and non climate related threats, such as fisheries, take, and coastal development. Through this information researchers were able to identify the world’s 13 least resilient marine turtle RMUs to climate change.
In response to the anticipated widespread negative effects of climate change, research has turned to primarily focusing on strategies that help alleviate some of the effects of the potential threats including the following: 1) mitigate the threat by reducing global green house emissions; 2) adaptively manage impacts from climate change by increasing population persistence; and 3) employ actions that build biodiversity resilience, such as addressing current non climate threats. Because reducing emissions is a big challenge and because immediate reductions will not necessarily stop the already unavoidable effects of climate change, researchers believe it is best to prioritize further research on attempting to predict the impacts of global warming until further information on the effectiveness of the above strategies is obtained. Thus an example of this future type of research can be viewed by further estimating how resilient populations or species can be under future scenarios such as that presented by Mariana Fuentes (2013) and her coworkers.
Experts were brought from several locations worldwide in order to assess each species of turtle used to calculate the RMUs for the resilience index. In some locations only one expert respondent assessed the RMUs of specific species of turtles given their natural habitat location. The RMU resilience index values ranged from a low of 0.89 (most resilient) to a high of 2.08 (least resilient). The variables most likely to influence the resilience of RMUs to climate change were rookery vulnerability and high climate threats. In other words species that suffered from the likelihood of extirpation of functional rookeries would not be able to recover from global climate change and those who suffered from non climate related threats such as fisheries would effect the resilience of RMUs to climate change as well. This can be used as an indicator of persistence of viable nesting in an RMU, given various threats and potential for range shifts over time. This is important because the importance of rookery persistence relates to the need for optimal nesting areas necessary for reproduction and thus recruitment entry into the population.
The ability to predict resilience among a species can help researchers find ways to protect species against environmental factors such as global warming. Because climate change is a major threat to biodiversity it is important that species find ways to overcome natural hardships in order to prevent entire groups of species from becoming endangered or even going extinct. The authors of this essay using an RMU resilience index were able to predict which species of marine turtles would suffer the most due to global warming. With the help of further more research humans can learn ways to help protect species as well. This is important if we want to find ways for species, including ourselves, to overcome the effects of global warming.
Fuentes, M.M., Pike, D.A., Dimatteo, A., Wallace, B.P., 2013. Resilience of marine turtle regional management units to climate change. Global change biology 19, 1399-1406 http://www.seaturtle.org/pdf/fuentesmmbp_2013_globalchangebiol.pdf