Tuesday, March 22, 2011

Eastern Red Spotted Newt

The Eastern Red Spotted Newt (Notophthalmus viridescens) has one of the most complex life cycles of any organism in the eastern deciduous forest.  The newt begins life as a larval resident of long-cycle vernal pools and semi-permanent ponds then, after one to two years of growth, takes to land as an immature "eft" for a period  of up to several years.  The eft stage is then followed by a return to the organism's native pool as an aquatic adult where it will spend the rest of its life.  Adult newts have dark brown to olive dorsal base color with bright red spots and a tan to cream ventral color.  Efts are smaller in length than adults with bright to dull orange base color and red dorsal spots. They are most commonly encountered on upland forested slopes following heavy rain events in summer months and can travel considerable distances from home pools.  Time wise, breeding activity of newts aligns with spotted salamanders and wood frogs so now would be a good time to observe.

A pair of adult newts doing the "hula dance".  Males (on top)
will grasp females and present a wiggling motion.  If the female
is impressed, the male will then deposit a spermatophore in front
of her on the pool floor which she can then decide to pick up
thus completing fertilization internally.  This female looks
like a recent metamorph due to her orangish base color
which will darken with age.

Long-cycle pools and ponds can have large populations
of newts.  Seven adults occupy roughly two square feet
of pool bottom in this photo.
An older eft found under a rock ledge.  Note the orangish base
color and red spots.  Recently metamorphosed efts often appear
much brighter orange.  A good time to find efts is during heavy
rains that follow dry spans in summer months. 

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