LOCAL SALAMANDER LIFE CYCLES

     Salamanders are slim, moist-skinned amphibians that shelter in water, or under rocks, fallen logs or leaf litter on woodland floors, depending on each species' life cycle.  Their clammy skins soak up water, and salamanders must stay moist, or they will die.  As adults, they all consume small invertebrates.  And each kind of salamander is attractive in its own, camouflaged way, though few people see them because they hide out so well.  

     Four common species of salamanders living in Lancaster County, Pennsylvania, represent four interesting life cycles of these amphibians.  Like all species of life, these kinds of salamanders, each finding a niche of its own, reduces competition for resources with other kinds of life, especially with close relatives.   

     Red-spotted newts are a kind of salamander that live as adults in ponds, and court and lay eggs on plants in those ponds.  The larvae hatch, grow lungs and eventually leave the water for life on woods floors as red efts, which are striking, red-skinned, immature newts with two rows of black-rimmed, red dots down their backs.  

     After a few years, red efts return to their impoundments to permanently live as adult newts, with camouflaging, olive-green upperparts, dotted with two parallel rows of red spots, and yellow underparts, sprinkled with tiny black dots.  But they still have lungs and must come to the surface of the water to breathe.  Newts may have returned to water as adults long ago because they couldn't tolerate competition for resources with their relatives on land.       

     Spotted salamanders are five-inch, black creatures with lungs, and two parallel rows of orange or yellow dots down their backs.  This species is an explosive breeder, suddenly emerging, in numbers, from woodland floor leaf covers during rains in February and moving slowly over soggy leaves to temporary, vernal ponds to spawn within a few days.  The gilled larvae ingest decaying plant and animal materials, grow lungs and leave their drying puddles for life in the damp leaf litter on forest floors.  When mature, they spawn in the same temporary ponds where they hatched.  But adult spotties always return to live permanently under moist,leafy carpets on woodland floors.  

     Three-inch, two-lined salamanders live in and along rock-bottomed, flowing brooks in northeastern North America woods.  They are a kind of lungless salamander, that take in oxygen and release carbon dioxide through their damp, or wet, skins.  Adults are yellow-brown on top, with two dark lines running along their backs.  

     Two-lined adult salamanders, and their larvae, live in slow pools of woodland brooks and under rocks in the currents of those same brooks.  There female two-lines attach eggs underneath the rocks for their safety against fish and crayfish.  Larval two-lines have gills, and are brown, which camouflages them.  Some adult and young two-lines are caught and eaten by garter snakes and water snakes.

     Red-backed salamanders are another kind of lungless salamanders that live exclusively on land.  This species has no aquatic stage in its life cycle.  Female red-backs attach their eggs to the sheltering undersides of rocks on forest floors; and they stay with those eggs to protect them.  The young hatch as miniatures of their parents, ready for life on land.

     Adult red-backs are about two and a half inches long, and many of them do have reddish backs; others have gray backs.  Since this species does not need water to spawn in, populations of them can live isolated in wood lots surrounded by farmland.  Presumably, no "migrating"red-backs can get in those woodlots, and none can get out.  Each population in a woodlot probably is small, with no additions to the salamander gene pool in that woodlot.  Those woodlot salamander populations, therefore, can produce knew kinds of salamanders because of a locked-in gene pool of relatives breeding with relatives, and developing quirks in the genetic code.     

     There are many other kinds of salamanders, each with its own interesting life history.  All species of life have interesting life histories, which makes nature intriguing to explore and study.   

            

 


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