Scientists suggest climate change could be the reason salamanders in the Appalachian Mountains are getting smaller.
In a study earlier this year in the journal Global Change Biology, researchers compared museum specimens of salamanders collected in the course of a half-century beginning in 1957 with those measured at the same sites in 2011 and 2012.
They measured almost 9,500 adult salamanders and found their bodies were, on average, about 8 percent smaller after 1980 than in the earlier decades.
The changes were most marked in the Southern Appalachians and at low elevations, settings where detailed weather records showed the climate has warmed and dried out most.
“One of the stresses that warmer climates will impose on many organisms is warmer body temperatures,” said Michael W. Sears, one of the researchers, in a news release. “These warmer body temperatures cause animals to burn more energy while performing their normal activities. All else being equal, this means that there is less energy for growth.”
Scientists said the reducing size of salamanders will have adverse implications for other predators. “Smaller salamanders mean other animals have to eat more, it will take more time to find food, and life becomes more difficult for everybody”. Salamanders are eaten by a wide range of species like birds, snakes, and small mammals, things like raccoons, possums, and shrews.
The salamander’s change in body size has been one of the fastest ever recorded, and researchers believe that this may show how other animals might adjust to different environmental conditions over time.
“We do not know if decreased body size is a genetic change or a sign that the animals are flexible enough to adjust to new conditions. If these animals are adjusting, it gives us hope that some species are going to be able to keep up with climate change,” concluded Karen R. Lips, the paper’s co-author, and an associate professor at the University of Maryland’s (UMD) department of biology.
The team says their next step is to study the similarities and differences between salamander species that are just shrinking – like those seen in North America – verses ones that are disappearing entirely from habitats that were once crawling with the tiny creatures.