Coping with increasing environmental temperatures: how vulnerable are amphibians to climate change?

TEJEDO, M.; DUARTE, H.; GUIÉRREZ-PESQUERA, L. M.; MARANGONI, F.; EGEA SERRANO, A.; SOLÉ KIENLE, M.

Cartajena

Congreso; X Congreso Latinoamericano de Herpetología; 2014

Global climate change over the coming decades is predicted to cause higher mean temperatures? an increased frequency of extreme climatic events? and changes in precipitation patterns. As ecological impacts will depend on both the magnitude and pattern of climate change and the thermal sensitivity of the organisms in question? it is crucial to better understand the mechanisms relating physiological function and ecological performance and to identify the species and communities currently exposed to higher risk of suffering physiological stress. We studied the thermal physiology of tadpoles from 71 amphibian species? from different climatic regions? by estimating their optimum temperatures using thermal performance curves and compiling information on their critical upper thermal limit. Furthermore? we determined warming tolerance and thermal safety margins for these species to assess their vulnerability to global warming. Our results indicate that species from tropical and subtropical warm communities are more vulnerable to suffer from acute (warming tolerance) and chronic stress (thermal safety margins) due to increasing environmental temperatures. Furthermore? although we obtained positive warming tolerance and thermal safety margins estimates? our data also shows that several species? including some from higher latitudes? already experience temperatures very close or even above their optimal performance temperatures. Hence? some species from temperate regions may also be negatively affected by global warming. This findings are particularly worrying since most of the amphibian biodiversity is located the tropical and subtropical regions. Moreover? since in this life stage they have very limited or no dispersal? amphibian tadpoles will have to rely on their ability to acclimate their thermal physiology and behavior changes (thermoregulation) to cope with the changing thermal environment.