RED-BACKED SALAMANDERS

     Not so many years ago, I entered woodlots surrounded by farmland here in Lancaster County, Pennsylvania to roll over small, moss-covered logs lying on dead-leaf covered floors of those small woods.  I did that to find red-backed salamanders living in dark, damp recesses under those logs.  Usually those salamanders quickly crawled under whatever remaining cover they saw and disappeared.  I always put the logs back carefully so as to not injure the salamanders.

     Red-backed salamanders are tailed, two inch amphibians that are slender and dull-red on top.  They live in moist, dark niches under logs, lichen-covered rocks, and carpets of dead leaves on woodland floors in the eastern United States.  There they keep their skins moist to live, and prey on small invertebrates.  If the skins of frogs and salamanders dry, they will die.  They only move out of their damp, dark homes during rains and on dewy nights to search for invertebrate food, and mates. 

     Amphibian means "two lives".  When youngsters, most amphibians have gills and swimming tails like fish for life in water.  But when they become adults, they have lungs and legs for life on land.  However, most of them must return to water to spawn many eggs per female.

     Red-backs, and their close relatives, have neither gills or lungs.  They take in oxygen and release carbon dioxide through their thin, moist skins, a reason they live in clammy darkness. 

     Red-backs, and their close relatives, have no aquatic stage in their life cycle.  They are not tied to water to spawn.  Each female red-back lays about twenty eggs into a cluster in the dark, moist retreat she lives in. There she protects her eggs until they hatch into babies that are miniature look-alikes of their parents.

     Not tied to water to spawn eggs, red-backs wander over woodland floors, at night or during rains, far from water.  They encounter many small, ground-living neighbors in those woods, including deer mice, short-tailed shrews, crickets, earthworms, slugs, millipedes, wood lice, click beetles, ants and many other kinds of critters. 

     Many red-backed salamanders live in remnant woodlots resulting from breaking up forests for fields, roads and buildings.  New species of salamanders probably are developing in some of those isolated patches of woods.  A change in the genes of a salamander that can only breed with others in its own small patch of woods could change that isolated colony of salamanders enough that it is regarded as a new species.  

     And because of the inhospitality of human-made habitats around each woodlot to salamanders, it is unlikely that an exchange of genes from one patch of woods to another happens.  Each little colony of red-backs is in a moist, wooded island, surrounded by a dry sea of development. 

     Red-backed salamanders are interesting, little creatures, particularly in their potential for developing new species.              

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