The Red Eft

Red Spotted Newt Juvenile ("Eft")
by Mary Furth

I was walking in Warbler Wood in Connecticut, searching for the owner of a raspy, but intriguingly varied bird call (turned out to be an Oven Bird) despite the muggy heat and the bugs that were almost oppressive.  Under the lofty canopy of this old growth forest, what little breeze there may have been was being absorbed by the old branches whose young leaves trembled providing dappled sunlight to the forest floor.  As I walked along the winding pathway, I noticed how large the wild violets were in comparison to the almost miniature scale of those found at this time of year in Maine.  I took a specimen to press and compare to my Maine specimens.  Around one bend, I noticed a small, bright red something sitting in the middle of the path in front of me.  It was a Red Eft making use of the shade provided by a cinquefoil leaf.  The bright red color and the bright spots outlined with black halos that lined its tiny back were striking. 

Red Eft
by Mary Furth

The Red Eft, also known as the Red Spotted Newt, or Notophthalmus viridescens, is the only newt found east of the Mississippi, and one of the two common newts in the United States.  Newts are far more diverse in Europe and Asia, and the Red Eft can be found in many of these places around the world.  In New England, it is especially common. 

(As an aside newts and salamanders are terms that are constantly interchanged, and have become confused.  It turns out, all newts are salamanders, because they are in the family Salamandridae, whereas not all salamanders are newts.  So it's ok to call a newt a salamander, but incorrect to call a salamander that is not a newt, a newt....)

Red-Spotted Newt Larvae
by George Grall

 When I think of a newt, I think immediately of a dull greenish or brown aquatic organism swimming around in a murky pond.  I never realized how different in appearance the three developmental stages of a newt are.  Newly hatched newts, (larval stage), look like delicate tadpoles with noticeably protruding, tentacle-like gills.  Just like tadpoles, newt larvae gradually develop four limbs, and the ability to breath outside of the water.  Soon they seek food and shelter on land, and with their newly found terrestrial livelihoods, they busy themselves with keeping spiders, flies, caterpillars and other bite-sized invertebrates in constant fear of their tiny lives.  And what's more, their bright orange color, which is only present in this juvenile stage, (in which it is known as an "Eft") reminds potential predators that they are toxic and inedible and thus perfectly invincible little critters.  

Because of their toxins, Red Spotted Newts have no predators.  The Western Newt, which is the only other newt found in the U.S., has one predator.  Incredibly, a few populations of garter snakes have developed a resistance to newt toxins.  A mutation in the snakes' genomes renders the newt toxin inadequate, which in turn applies selective pressure towards newts with higher levels of toxin.  In this "evolutionary arms race", the snakes continually respond to selective pressures which produce populations of continually more resistant snakes. 

Red Spotted Newt Adult
By Gary Nafis

In the third stage of the newt life cycle, a second metamorphosis occurs, and the newt returns to an aquatic lifestyle, rarely, or never again to venture back onto land.  At this point, the red spotted newt's bright orange/red skin has changed into a yellowy, greenish-brown.  It keeps it's limbs and develops external gills once more.  It is no longer called an "Eft".  Despite the fact that the adult stages has less than vivid coloring, the red spots encircled by their black halos persist to warn of their toxicity, which is lethal to predators who attempt to ingest them.  

The red spotted newt is one of the few that is merely toxic through ingestion.  Newts are often thought of as extremely toxic because in most cases,  one must only touch their skin to feel the effects of their toxins.  Therefore, Red Spotted Newts may be handled gently, with no adverse effects to a curious amateur naturalist. 

Red spotted Newts are pretty to see, especially in their juvenile, "Eft" stage, but they are also important as an indicator species.  Literature suggests that Red Spotted Newts are "area sensitive" (Hager, 1998), meaning that they were absent on smaller islands, but present on larger ones.  As a result, these newts may be a good indicator of habitat fragmentation.  As habitat is used for development and destroyed with deforestation and pollution, the land is in effect divided into islands. The presence or absence of the Red Spotted Newt may give scientists an idea of the extent to which habitat fragmentation is effecting wildlife.  

For more information, refer to this bibliography and the accompanying website: Notophthalmus viridescens