Bird Food in Winter Seepages and Trickles

     Clear water percolating from the ground in several of Lancaster County, Pennsylvania's short-grass cow pastures creates many varied-sized, shallow seepages and running rivulets free of ice and snow.  Moving water doesn't freeze easily, and doesn't allow the accumulation of snow on it.  Those green oases of trickling water, mud, lush short-grass, water cress and algae, surrounded by snow at times in winter, draw a variety of wintering birds seeking food when their usual sources are buried under  snow and ice.  Those same birds add beauty and interest to the seeps and trickles.
     Groups of Canada geese, mallard ducks, black ducks and American wigeon ducks feed on the grass, cress ad algae in those seepages and tinkling trickles snaking darkly through the snow cover when their usual food of corn kernels and green rye shoots in the fields are buried and ponds are frozen shut.  The geese and wigeons pluck the grass with their sturdy beaks while the mallards and black ducks shovel up the soft water plants.  That division of food sources reduces competition among those related waterfowl.
     Those mixed gatherings of geese and ducks are attractive and interesting.  The large geese appear stately, while mallard drakes have iridescent green heads and black ducks do look black against the snow, though they are dark chocolate in color. 
     Other kinds of wintering birds are on those little islands of clear, ice-free water, mud and lush vegetation, bordered by a sea of snow cover, to consume invertebrates in the water and mud.  Those birds include one or two each per seepage of Wilson's snipe, which is a kind of inland sandpiper, killdeer plovers, American pipits and song sparrows.  All these little birds are brown and striped beautifully on top to allow them to blend into the background of mud and short vegetation to be safer from predation.  Most of the time they can't be seen until they move; and then one needs to know where to look to spot them.  But when noticed, one has to admire their attractive plumages. 
     Several snipe feed from these seeps and trickles in meadows all winter, whether snow is on the ground or not.  They are the most endemic bird at these seeps and trickles through each winter.  But more of them are in that niche when other shallow waters freeze.  Snipe get food  by rapidly poking their long beaks into mud under shallow water to pull out worms, snails, insect larvae and other aquatic invertebrates still active because the running water keeps them warmer.  The quick, up and down action of a snipe's bill is like that of a sewing machine needle. 
     Killdeer, pipits and song sparrows walk on the mud's surfaces and the water's edges to get invertebrate food, again kept active by the running water that laps over the mud and tiny shorelines.  Those birds might compete with each other for food, but not with the snipe. 
     Little flocks of American robins, American crows and ring-billed gulls sometimes land on larger  seepages in short-grass meadows to ingest invertebrates, but not all at once.  These birds in their numbers and sizes probably clean out much of the invertebrates in a seep or trickle, making life tougher for the snipe and other smaller bird species at the seeps.  But the robins, crows and gulls usually don't stay long at any one seepage or rivulet. 
     When snow covers the ground in Lancaster County farmland, watch for birds around seeps and trickles of snow and ice-free, clear water.  You will know that those birds are there to get food until there normal, larger food sources again become snow-free.