WINTERING VOLES AND LARKS

     The disturbances of plowing, planting and harvesting large acreages of open cropland in Lancaster County, Pennsylvania make a tough, human-made habitat for wildlife to permanently live in.  And winter conditions make it even more difficult for those wild creatures to live exclusively in big, cultivated fields with few trees and fewer hedgerows to provide shelter against severe weather and predators.  But field voles (mice) and sparrow-sized horned larks live abundantly in cropland with little cover the year round.

     Field voles are chunky and short-tailed, with gray-brown fur and small eyes.  They live and raise young in chewed-grass nests in little burrows in the soil of fields, and along rural roadside shoulders and banks.  Roadsides are mowed occasionally, but not plowed, allowing seed and berry-bearing plants time to grow to maturity and bear their fruits, many of which are consumed by mice.  Voles also ingest corn kernels and cereal grains they find on the ground of nearby, harvested fields.

     When snow covers fields and roadsides, voles tunnel through the flattened grass, under the protective snow cover.  There they are partly safe from red foxes, owls, American kestrels and other kinds of hawks who can't see them, but can still hear them moving about under the snow.  Kestrels watch and listen for voles from roadside wires and poles and foxes crash through the snow in hopes of grabbing a fat mouse.  

     When the snow melts away, grassy runways, chewed-out by the mice, are clearly visible on the ground. Those grass-walled tunnels, without their snowy roofs, are evidence of the voles' presence.  And now voles must again resort to underground holes to hide from predators.

     Horned larks are the only local birds to thrive the year around on open cropland, even wintering and raising young on them.  Hundreds and hundreds of wintering horned larks, in flocks, are regularly the most abundant birds on Lancaster County fields that were harvested to the ground, though those little birds are never seen by most people.  

     Being brown on top, the small horned larks walking over bare, or nearly so, soil, are camouflaged on vast farmland.  They are only visible when taking flight, particularly along country roadsides.

     Horned larks are most commonly seen after a snowfall, which covers grains and seeds in the fields.  Then flocks of these tough, little birds bound in flight, low to the ground, across wind-swept fields to plowed roadsides bordering those fields, to look for seeds and grain, and bits of stone to help grind those hard foods in their stomachs.  

     The larks land along country roads where snow plows uncovered soil, stones and seeds by the sides of those roads.  The birds consume exposed seeds and grit there until the fields thaw, exposing food. 

     Being right along those rural byways after a snowfall, and flying up before approaching vehicles, people see how attractive horned larks are.  They have yellow and black patterns on their faces, with black moustaches, bibs and feathered "horns".

     When snow covers farmland, the handsome horned larks also visit strips of manure spread across fields.  There they scratch out many bits of corn that was chewed by livestock, but not digested.  Corn in manure is a great source of sustenance until the snow melts.   

     Falcons, including kestrels and merlins, fly fast enough and are maneuverable enough to chase horned larks in flight, kill, and eat them on open, windy croplands.  

     Clods of soil or snow drifts are the only shelters wintering horned larks need in open fields.  These tough, little birds squat on the leeward side of those sparse shelters to wait out the cold nights.  

     By mid-March, horned lark flocks disperse, males sing lovely, tinkling songs while hovering in the sky and pairs of them dig tea-cup sized holes in bare soil for their first clutch of eggs.  Parents, eggs and young blend into the bare ground as a defense against foxes, crows and other field predators.  And if a lark cradle is destroyed by cultivation, the larks simply start another one, and another, until they get at least one brood to flight. 

     Field voles and horned larks have adapted to cultivated habitats with little cover.  Most every niche on Earth has at least one species of life adapted to it.  

        

                       

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