Most amphibians lead dual lives, beginning in the water as jellylike eggs that hatch into gilled, swimming larvae and metamorphosing into adults with lungs, four legs and the ability to live on land. That remarkable life cycle, which is dependent upon clean, healthy aquatic and terrestrial habitats, puts them at double risk as Earth’s climate changes.
A changing climate means more variability not just in temperature but also in precipitation. In regions where average annual temperatures are rising and rainfall is declining, ephemeral ponds, where many amphibians breed, and permanent wetlands, lakes and streams, where young and adults might live, are in danger of shrinking or disappearing. (And this is on top of ongoing habitat loss from development.)
Unpredictable temperatures from season to season and year to year can also disrupt an amphibian’s internal clock. Scientists have documented shifts in the timing of amphibian breeding due to climate change. Research in the Northern Hemisphere showed that amphibians have shown a stronger shift toward earlier breeding than all other groups that were studied. In fact, amphibian reproductive seasons moved up on the calendar at a rate that was twice as fast as those of birds, butterflies and even trees. Eggs might hatch too early for larvae to find their tiny prey.
Right now, climate change is not considered to be a major cause of the declines or extinctions of amphibian populations worldwide. But weather patterns are changing from historic trends, resulting in drier summers, increasing average annual temperatures, shorter winters and more intense and frequent storms. And these changes are happening faster than amphibians—along with other wildlife and even humans—might be able to adapt to a new environment.
Make a change to help
Reduce your use of fuels that contribute to climate change. Turn off lights, keep your home a little cooler in winter and warmer in summer, and conserve gasoline by driving less, turning off the engine instead of idling, and buying a fuel-efficient car. And reduce, reuse and recycle plastics—they’re petroleum products!