Wednesday, August 3, 2016

A Common Newt

The terrestrial juvenile or eft stage of Notophthalmus viridescens


 If these eastern red-spotted newts are so common, it seems like we would see them more frequently.  Perhaps one reason we don't is because they live an elusive  life that involves extreme transformations --  changing color and appearance with each life cycle.  Larvae and adults rely on gills to obtain oxygen from the water, while terrestrial juveniles have lungs.  Members of the salamander family, they begin life in the water, leave for a few years to live on land, and then return to live in water. 

In the early spring, females lay eggs in a pond or other quiet body of water.  Weeks later small, brownish larvae hatch and spend the summer in the water.  In late summer they grow into orange efts, or juveniles, like the one pictured above, and leave the water to spend up to three years on land in woodland habitats.   Once they reach maturity, they return to the water to breed, and then spend the rest of their adult lives living in the water. Aquatic adults can reach five inches in length and are greenish brown but retain their juvenile spots. They can live for more than 10 years. 

The bright orange of the juvenile stage is a warning color to predators.  If attacked, their skin can secrete a toxic substance to discourage most predators from eating then.  Efts often move around at night but can be seen in the daytime when the ground is moist.  Efts eat worms and insects that can be found in leaf litter.

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