Climate change represents a real threat to the environment and, according to a study published on April 9 in the Proceedings of the Royal Society B, it has already made its first victim, namely the coqui frog, that could become extinct if the female animals do not alter their hearing in order to pick up the males’ changed chirps. Rafael Joglar, professor of biology at the University of Puerto Rico added that, as temperatures rise, the fungus Batrachochytrium dendrobatidis causes fatal skin infections which could kill one of the territory’s symbols, namely the small brown tree frogs. Scientists also believe that global warming could be responsible for the disorientation of the bats and marine mammals, since the ocean acidification could cause low-pitched sounds to travel farther under water.
UCLA biologist Peter Narins’ first study which aimed at analyzing coqui frogs’ chirps differs from the one carried out in 2006, so the expert concluded that climate change might be making its first victim. At the same time, Joglar believes that the rising temperatures affect not only the sounds the animals make, but also their life, since they help fungus develop which, in turn, kill the frogs. Climate change is responsible for increased temperatures and, since the coqui frog appears to get shorter and higher pitched, Narins wishes to recreate the original study carried out in 1986 to conclude whether the changes in Puerto Rico’s coqui calls are undoubtedly related to changes in temperature.
Coqui frogs received their name because their calls include a “co” note and a “qui” sound. While the “co” is a warning to other males, the “qui” allures local females. Narins discovered that the “qui” notes vary with altitude, but recent studies have determined him and other experts to believe that climate change has made its first victim, namely the coqui frog, which must adapt to the temperature adjustments in order to survive. In his original study, Narins concluded that frogs living closer to the sea level differ from those that are located at higher elevations. However, when he carried out a similar study in 2006 with his colleague Sebastiaan Meenderink, they found that the frog calls heard in both regions were different after 20 years. Narins believes that, because of the climate change, the animals will grow even smaller and “their calls will be higher pitched than they are now,” while their duration will also shrink.
Narins believes that, apart from the petite size of the frogs, the alterations climate change brings about must be embraced by the female coqui frog; if its inner ear adapts to the changes, the species could survive. However, if they disappear, they will also destabilize the local food pyramid. As a result, Joglar believes that there will be no more species of frogs to eat the mosquitoes, which could mean that people will be more exposed to the diseases they carry, such as dengue fever and malaria.
Although long-term studies of how frogs change from a physical point of view are uncommon, Narins is set to continue the study began in 1986 in order to predict the impacts of global warming. So far, reports show that climate change has made its first victim, namely the coqui frog, which is now smaller and its calls are higher pitched.
By Gabriela Motroc