By Jim Knox
Wildly Successful: The Eastern Newt
“I found one Dad!” My son excitedly called from the stream at the base of the spillway.
“There’s one there too! And another one! Dad, they’re all over the place!” he announced in amazement.
I followed his gaze to see the creatures capturing his attention. There, just beyond his outstretched arm and pointing index finger, were small green salamanders clustered at the head of the stream–dozens of them. What we’d found that sunny spring day on our hike in the woods of Fairfield County was a congregation of native Eastern newts. Much like toads are dry, bumpy-skinned species of frogs, newts are dry granular-skinned species of salamanders.
The Eastern newt, (Notophthalmus viridescens) is one of our most recognizable and well-known amphibians, yet it holds mysteries which continue to elude science.
The adult newts we found swimming and hunting in the stream’s cool shallow waters that day were beautiful animals. At five inches long with deep green backs, golden bellies and broad, flattened, sculling tails, they caught our eye. Black “masks” extending from their snouts through their eyes to the back of their jaws marked them boldly. Fine black speckles cloaked with an overlay of an irregular twin row of ruby red black-bordered spots adorning their backs completed their appearance. In fact, the species’ scientific name is Greek for “back eye”, referring to this striking feature.
While these creatures are known to many, most hikers do not know their connection to another, even more striking amphibian. The forest-dwelling counterpart to these stream and pond-dwelling amphibians known as the red eft, is hard to miss. The three-inch-long eft ambles through deciduous and coniferous forests advertising its travels. Unlike fellow tiny woodland creatures which scurry and hide, these granular-skinned brilliant red-orange newts explore their world with near impunity. They can do so due to the potent toxin hidden within their glands and skin.
These little beasts roam the woodlands–especially after rainfalls–exhibiting aposematic or warning coloration. By advertising their powerful toxin, known as tetrodotoxin, they avoid predation from nearly all woodland predators. If you look closely, you’ll notice a twin row of familiar-looking ruby spots with black borders adorning the backs of these little land-dwelling salamanders…and there’s our connection.
The Eastern newt undergoes metamorphosis and exhibits multiple life stages. Hatching from eggs in the spring, the half-inch-long, green-brown larvae or tadpoles possess gills to breathe underwater. Once they transform in the fall to a four-legged land form–the red eft–they are equipped to leave their home wetland. This radical transformation confers the ability of these little amphibians to travel great distances overland to disperse, colonize new wetlands, expand their territory and outcross their genetics. In short, this inborn wanderlust of three to four years, enables the newts to introduce their genes to new populations, increasing genetic diversity and protecting individuals from local diseases or environmental conditions.
After their long forest journeys of up to four years, the efts “settle down” in new wetlands and transform into the green and gold Eastern newts we encountered that sunny morning in the spillway stream. This adult stage of the newt is accompanied by a surge in length, weight and a large, laterally-flattened sculling tail which propels the newts through the water to both seize prey and evade predators alike.
Regardless of their life stage, like their fellow amphibians, Eastern newts are strict carnivores. Consuming amphibian eggs, insects, snails, aquatic crustaceans, worms, leeches and the occasional small fish, if it moves and it can fit into a newt’s mouth, it’s on the menu!
Employing a different strategy than their tadpole and adult incarnations, the efts benefit from an exponential boost of tetrodotoxin 20 times that of its adult stage, protecting them from amphibian, reptile, bird and mammal predators alike.
So what does this beautiful, adaptable and toxic little amphibian hide from the ever-searching eyes of science?
While we have been able to unlock the newt’s astounding attributes, one tantalizing trait hints at an amazing ability. Eastern newts are known to possess uncanny orientation homing ability, facilitating their travels within their forest habitats. Utilizing suspected sunlight orientation in combination with our planet’s geo-magnetic properties, the tiny creatures are able to successfully navigate vast distances relative to their size.
At the core of this ability is the poorly understood link to naturally occurring traces of Magnetite–an iron ore and one of the planet’s most magnetic naturally occurring minerals–within the newt’s bodies which enable them to align with earth’s magnetic fields. Study by such prominent academic institutions as CalTech, offers to shed more light on this ability, which could aid our species in innumerable ways.
While the newt promises to aid us through scientific discovery, we owe our slimy friends the benefit of protection in exchange. Right here, in Fairfield County, our amphibian neighbors face pressing threats such as habitat fragmentation, introduced invasive species and climate shift, which compromise their survival. Whether it be through promoting education and conservation through organizations such as The Greenwich Land Trust or The Bruce Museum, or through enhancing habitat on your own property to achieve Backyard Habitat Certification through The National Wildlife Federation, there are things each one of us can do to make a difference.
In The Eastern newt we have a backyard species which possesses innate abilities which have protected it for untold generations and offer to expand our scientific knowledge and well being. So if you’re lucky enough to glimpse one of these little red guys wandering the vast green of the forest, I’d suggest you follow because, rest assured, he knows exactly where he’s headed.
