A black-chinned red salamander in Georgia. (Photo: Todd W. Pierson/University of Georgia)
My latest for the New York Times:
If someone asked you to name the top predator in North American forests, you might think of bears, or maybe great horned owls. But here’s another answer to think about: woodland salamanders.
These skittish, slippery amphibians literally live under a rock, or a log, or any convenient dark and damp forest habitat. As apex predators go, they are mainly small, a few inches long and weighing well under an ounce.
But they are hugely abundant — and very hungry. On an average day, a salamander eats 20 ants of all sizes, two fly or beetle larvae, one adult beetle and half of an insect called the springtail. And in doing so, they collectively affect the entire course of life in the forest — and perhaps far beyond.
According to a new study in the journal Ecosphere, salamanders play a significant role in the global carbon cycle. If flatulent cattle are among the black hats of climate change (the livestock industry emits 14.5 percent of human-associated greenhouse gases), then salamanders may just be the white hats, helping to stave off climate disaster. If no one has noticed this before, well, this is how it goes when you live under a rock.
A painted ensatina in northern California. (Photo:
Todd W. Pierson/University of Georgia)
The study — by Hartwell H. Welsh Jr., a herpetologist at the United States Forest Service’s research station in Arcata, Calif., and Michael L. Best, now at the College of the Redwoods in Eureka, Calif. — notes that salamanders’ prey consists almost entirely of “shredding invertebrates,” bugs that spend their lives ripping leaves to little bits and eating them.
Leaf litter from deciduous trees is on average 47.5 percent carbon, which tends to be released into the atmosphere, along with methane, when the shredding invertebrates shred and eat them.
If there aren’t as many shredders at work and the leaves remain in place, uneaten, they are covered by other leaves, “like being trapped under a wet blanket,” as Dr. Welsh put it. The anaerobic environment under those layers preserves the carbon until it can be captured by the soil, a process called humification.
At least in theory, having more salamanders in a forest should mean Read the rest of this entry »