Three Salamander Lifestyles

     Salamanders are amphibians and the word amphibian means two lives.  Most amphibians start life in water like fish, but later leave the water and live on land, only returning to water to spawn.  But not all salamander species follow that lifestyle.  Some species developed other ways of living to adapt to their respective niches and survive.  Here in southeastern Pennsylvania, spotted salamanders, eastern newts and red-backed and slimy salamanders represent three salamander lifestyles.
     All adult amphibians (frogs, toads and salamanders) are predatory, feeding on creatures they can handle, which mostly is invertebrates.  And all amphibians in this area are small and hidden away in damp places to keep their bodies moist for survival. 
     Spotted salamanders, a kind of mole salamander, are called that because they live in the ground under carpets of fallen, dead leaves in forests in eastern North America.  They start life with four legs, swimming tails and external gills in vernal ponds where their parents spawned during rainy days in the woods in March.  But after a few months living in water, they come out onto the land where they spend the rest of their lives, except to spawn milky-white, gelatin-like masses, with several eggs in each one, in the same woodland pools they hatched in.  
     The attractive adult spotted salamanders are up to six inches long and black with two rows of yellow or orange spots down their backs.  They are seldom seen, except when spawning or marching across forest floors to pools during rainy March nights.
     Eastern newts, another kind of salamander, have three stages in their life history.  These newts of the eastern United States start life in water as brownish larvae, each with four legs, two external gills and a swimming tail.  But after several months, they emerge on land, become striking reddish-orange with red spots, each one thinly ringed with black.  The bright color of these red efts warn predators that efts taste bad.  
     After two or three years of living in moist places on land, efts return to ponds, transform into beautiful adults that are olive on top with red spots, yellow below and covered all over with black dots.  There they live the rest of their lives, and spawn there as well.
     I think eastern newts took that third step in their life cycle because they couldn't compete for space and food with their relatives on land.  So they gradually created their own niche as adults living in water, where they have lived ever since.  But they still need to come to the surface to take oxygen from the air.
     The ancestors of the related red-backed and slimy salamanders may have adapted to damp forest floors where there was no standing water to spawn in.  Over time, they developed the habit of laying clutches of up to a dozen eggs, each with a thicker, more protective covering, in moist, protective places under rocks, fallen logs and leaves, and other objects on forest floors.  Today the young of red-backs and slimies don't pass through an aquatic phase, but hatch on damp soil in humid places as miniatures of their parents.  These species of salamanders are not tied to water to reproduce, which allows them to spread farther and farther across wooded landscapes.
     Red-backed and slimy salamanders could even be creating new species by being isolated in islands of woods, surrounded by seas of fields, lawns and other human-made habitats not beneficial to salamanders.  The salamanders can't travel over those dry environments to exchange genes.  Any genetic quirk that aids survival in a woodlot would stay in that patch of woods, creating a new species in that woodlot only.  These salamanders survive in tiny woods, even without pools of water, because they have long ago adapted to spawning on moist soil in shaded, protective niches. 
     These three kinds of salamanders in southeastern Pennsylvania, as examples, demonstrate three successful lifestyles.  It pays for any form of life to diversify as much as possible to use as many niches as possible.