Streambank Homes

     Late this morning, as I was driving home through Lancaster County, Pennsylvania farmland after a couple of errands, I crossed a clear stream and noticed a muskrat swimming in it.  I stopped the car by that waterway and watched the muskrat exit the water and walk up a streambank to a meadow of short grass.  There it pulled up grass with its teeth, then waddled back down to the stream with a wad of short grass in its mouth and swam upstream for several yards.  Then that rodent with a beautiful fur coat dove under water and swam into a hole in the streambank at the water level.  The muskrat made a few more trips of that nature while I watched.  Perhaps it was a pregnant female making a nest in her den for her future babies.
     The stream the muskrat lives in flows through a short-grass cow pasture, studded with large willow and silver maple trees.  The day has been cold and windy, but clear with ample sunshine.
     As I waited for the muskrat to show herself, and while watching her, I saw a small variety of wintering birds around that waterway.  A pair of eastern bluebirds were flitting among twigs in one of the willows, while a small group of American goldfinches fed on weed seeds on a south-facing streambank along the waterway.  Meanwhile, a little group of American pipits walked about on the short grass meadow, back a few yards from the waterway, in their search for tiny invertebrates among the grass roots to eat.  The bluebirds and goldfinches might be local birds, but the pipits are down from the Arctic tundra for the winter.
     And while watching the muskrat, I was happy to notice a red-tailed hawk soaring majestically on high.  That diurnal raptor probably was watching for mice, squirrels or any other creatures it could attempt to capture for a meal.  And a bit later, from the same spot by the waterway, I was thrilled to see a magnificent adult bald eagle soaring low over the surrounding cropland, possibly in search of carrion to ingest.  Sometimes, several bald eagles winter in Lancaster County farmland to feed on dead livestock deposited on the fields.
     I also saw a great blue heron, about a hundred yards back the stream, wading in the water to catch fish.  And I noted a male belted kingfisher flying from tree limb to tree limb along the waterway.  Kingfishers, too, catch fish by diving into the water from a tree branch or hovering into the wind.
     As I watched the muskrat and kingfisher along the stream, I thought about how these species live and raise young in burrows they dig themselves in streambanks.  Muskrats excavate burrow entrances at the usual water level, then tunnel up to a living chamber just under the grassroots level.  These rodents, therefore, exit their tunnels in relative safety underwater and their living sections are far above the water line so the owners don't drown during floods.
     Muskrat burrows are generally safe from most predators, but mink, which are semi-aquatic weasels, get into some muskrat dens, kill and eat the resident or residents and use the 'rats' homes for themselves.  Some female mink even raise young in muskrat burrows.
     Kingfisher pairs dig burrows near the top of streambanks, tunneling straight back a few feet to a nesting chamber.  Their each pair rears several offspring on fish and other aquatic critters they catch in waterways and impoundments. 
     Pairs of rough-winged swallows use some abandoned kingfisher holes to raise their own youngsters.  They feed their offspring on a diet of insects they catch in mid-air.
     Muskrats and kingfishers live and raise young in tunnels they dig into streambanks.  Those burrows are relatively safe to the creatures that created and use them, species that demonstrate how most every niche on Earth is occupied by some form of life.