When one thinks about top predators, lions and tigers and bears (oh my!) are likely to be some of the first to come to mind. However, there are much smaller carnivores in our forests that play a very important ecological role.
Salamanders are one of the most abundant vertebrate predators in North American forests. These small, slippery amphibians spend most of their time under rocks and other dark, moist places, but they are actually voracious predators with a huge appetite, consuming about 24 insects a day.
Their prey consists almost entirely of “shredding invertebrates”, which tear leaves and other forest litter into tiny bits and eat them. This process releases the carbon stored inside the leaves into the atmosphere.
By eating the shredders, more of the leaf litter stays on the forest floor, becoming a damp, insulated blanket that traps the carbon until it can be absorbed into the soil (a process called humidification).
Local scientists Hartwell H. Welsh, Jr. and Michael Best published a study examining the role of salamanders in the carbon cycle in the journal Ecosphere. The results were surprising, and recently featured in an article in the New York Times (NYT) (“Salamander’s Hefty Role in the Forest”, April 7, 2014). By extrapolating the results of their study plots to a larger scale, they discovered the amount of carbon stored (verses being consumed and released) is enough to have an effect on the global climate.
“It’s more than just a curious phenomenon,” Dr. Welsh states. “It’s real.”
Best also previously published an article on his findings in the June/July 2011 issue of EcoNews (available on our website at www.yournec.org).
The cost of living is not very high for salamanders. All they need is a moist and cool place to hide while they wait for invertebrates to walk by. If the location is productive, the salamander may sit there all night long; if not it will wander on until deciding to stop elsewhere. The process is efficient—no venom, no chase, no big show; no wasted energy.
Also, the salamander body is very low maintenance by design. Because they are ectothermic—they heat and cool their bodies from the environment, rather than from the inside—no energy is used to regulate body temperature. If conditions are not favorable (too hot, too cold, too dry) they just stay within their cool, moist home, in sleep mode, until the weather changes. When the air is cool and moist, salamanders spend most of their time eating.
These little unsung heroes play a dynamic role in carbon sequestration on the forest floor, so tread lightly—the world beneath your feet is alive!