Wildlife Along Meandering Streams

     Many waterways throughout the world meander across the landscape, winding (turning) here and there along the way.  The faster-moving water on the outside of the curves washes away some of the waterways' bordering soil, creating tall, 90 degree-angled stream banks.  But the slower water on the inside of each bend in waterways dumps mud and gravel from upstream, which builds up mud flats and gravel bars.  A small variety of wildlife here in southeastern Pennsylvania takes advantage of the turns in smaller, inland waterways to find food and shelter.  They are examples of life throughout the Earth doing the same.
     Individual pairs of belted kingfishers and individual muskrats dig protective burrows into tall stream banks, the kingfishers near the tops of them and the muskrats at the normal water level.  Kingfishers use their deep tunnels to raise young, feeding them crayfish, small fish, tadpoles, aquatic insects and other little, water creatures.
     Some abandoned kingfisher holes in stream banks are used by pairs of rough-winged swallows for rearing offspring, though they are perfectly capable of digging their own little burrows in stream banks when they have to.  Like all swallows, rough-wings fly about catching small, flying insects, which they also feed to their youngsters. 
     Muskrats dig tunnels at the streams' water levels, then up to a den just under the grass roots level to be above most water levels.  There they live, safe from most predators; and there females raise litters of young.  Mink, which are a kind of weasel, enter muskrat burrows, kill the occupant, or occupants, and live in the dens themselves.  And there female mink raise young.
     Mud flats and gravel bars created on the inside of the bends in waterways because of a slower current are places where a couple of kinds of birds hatch babies and where a limited variety of wildlife search for food.  Killdeer plovers and spotted sandpipers, both species of inland shorebirds, lay four eggs per brood on gravel bars.  Though those eggs are exposed, they and their brooding parents and resulting precocious chicks are well camouflaged on the gravel.  Killdeer and sandpiper families also roam the gravel bars and mud flats in their search for invertebrates to eat.
     Other kinds of critters also use gravel bars and flats on the inside of stream curves in meadows to watch for edibles.  Late in summer, little groups of migrant least sandpipers, and individual solitary sandpipers and lesser yellowlegs, walk over the flats in their quest for invertebrates.  Song sparrows do that through the year.  At times, a small variety of herons, including great blue, green and black-crowned night herons, and great egrets stalk fish and frogs in shallow water just off the gravel bars and mud flats.  A few each of Wilson's snipe and American pipits also feed on invertebrates from streamside mud flats, but not in summer because they breed farther north.  And raccoons and mink use the flats at night to get prey animals, including fish, frogs, crayfish, fresh-water clams and other edibles on the flats and in bordering shallows.
     A couple other kinds of birds use stream banks and gravel bars in woodlands.  The camouflaged Louisiana waterthrushes raise young on ledges in the soil of streambanks.  These warblers catch invertebrates from under stones on the edges of woodland streams and brooks.  They feed those same foods to their young in their streamside nurseries.
     Winter wrens winter along small waterways in the woods.  There they prowl the water's edge like feathered mice in search of tiny invertebrates kept active by the flow of water.  These wrens blend in well with the dead leaf carpets, logs and brush piles on forest floors, places where they also hunt for invertebrates to eat.
     These are a few examples of life adapting to every niche, natural or human-made, on Earth.  It's no wonder there are so many different species thriving on this planet.  And to be adaptable is to survive.