One recent June afternoon, while scanning the opposite shore of a clear-flowing stream with binoculars, I saw a few handsome painted turtles sunning themselves on that stream bank. And as I admired the red and yellow stripes on those turtles' necks and front legs, I heard a chorus of green frogs belching from the same waterway. Again using binoculars, I saw a few of those google-eyed frogs half-hidden in the blobs of algae in still water along the stream's shoreline.
Certain kinds of amphibians and reptiles are declining in numbers in southeastern Pennsylvania, but other species seem to be holding their own here, including in slow stretches of flowing streams and creeks in this area's farmland, a human-made habitat that is not ideal for herpetofauna to live in.
People generally think of these creatures living in ponds and marshes of standing water, and they do. But green frogs, bull frogs, Fowler's toads, painted turtles, snapping turtles and northern water snakes have adapted to residing in the more placid currents of smaller, fast-running waterways, which increases the living space, food resources and numbers of these aquatic creatures. These amphibians and reptiles are the most omnipresent and readily seen and heard in local waterways.
All these creatures are cold-blooded, so they are dormant and hidden away in winter. But they are active and noticeable in the warmer days of each year.
All these herps are greenish or brownish; well camouflaged, which blends them into their habitats for their own protection against predators, including herons, mink, raccoons and other species. And these amphibians and reptiles are secretive, and quiet for the most part. They hide in shoreline vegetation where predators usually can't see them.
However, painted turtles and northern water snakes regularly bask in sunlight on rocks, shorelines and limbs fallen in waterways. They do that to warm up to have the energy to hunt food and mates. But basking can make those creatures more visible.
Female snakes that give live birth also bask in sunshine to provide warmth for the growth of embryos inside them. Female water snakes generally give birth by the beginning of September.
All these critters, except painted turtles, are totally carnivorous. Frogs and toads ingest invertebrates, snapping turtles consume fish, ducklings and other creatures, and water snakes eat frogs, tadpoles and small fish. Painted turtles ingest water snails and other small creatures, but also lots of aquatic plants.
These species of herpetofauna have different ways of reproducing. Male frogs and toads either croak, moan or trill in slow, shallow water, according to their kind. Each female frog or toad spawns hundreds of eggs in gelatin-like blobs or strings, again according to its type, in sluggish water. Turtles, however, lay eggs in holes they dig in the soil near the water they live in. June is when most turtles lay eggs.
These kinds of herpetofauna do live in quiet water in southeastern Pennsylvania cropland. But they also dwell in slow parts of streams and creeks here, which has helped maintain the populations of these amphibians and reptiles. Adapting is a key to success.
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