Birds on Atlantic Beaches and Jetties in Winter

     Five kinds of birds regularly winter on the beaches and rock jetties of the Atlantic Coast.  And in winter, they all feed on small crustaceans, molluscs, insects, worms and other invertebrates on the sandy beaches and boulders piled at 45 degree angles from the beaches to protect their sand from wave erosion.  But they do so on different parts of those habitats, and by using different, interesting techniques, which reduces competition among them for food.  The five species are sanderlings and dunlin, which are types of sandpipers on the beaches, and purple sandpipers, ruddy turnstones, which are another kind of sandpiper, and harlequin ducks on the jetties.
     Sanderlings are light in color in winter to blend into the background of sand to be nearly invisible, until they move.  Camouflage on creatures protects them from predation.  
     Sanderling flocks run up the beaches ahead of incoming wavelets, but quickly turn around and chase those same little waves when they slide down the beach to the ocean.  Sanderlings pick up and eat tiny invertebrates stranded in the foam on the sand as the water recedes.  And it's entertaining to watch their curious way of feeding.
     Also the color of sand in winter, gatherings of dunlin mostly get their invertebrate food on beaches by probing into the sand with their sturdy beaks.  Dunlin constantly move about, mostly by flying into the wind low to the sand as a group, as they deplete food in the parts of the beaches they visit.
     Purple sandpipers are not purple, but a bit dark like the boulders they live on in winter, which camouflages them.  They really can not be seen until they move.  This kind of sandpiper walks individually or in tiny gatherings over the boulders and consumes invertebrates already on them, and those dumped by waves splashing almost constantly over the rocks.  
      Ruddy turnstones are white and chocolate in color in winter.  Their color patterns break up their shapes, making them difficult to see.  They, too, walk on the boulders, flipping over stones and shells with their strong bills to grab invertebrates that might be hiding under them, something the purple sandpipers don't do to get food. 
     Harlequin ducks repeatedly dive under water near the jetties to get invertebrate food at the bottom of the shallow water, but soon pop up again to get air.  They also must be careful not to be dashed against the rocks by the waves.
     Harlequin drakes are small, beautiful ducks, with gray, chestnut, black and white feathering in striking patterns that also break up their patterns for camouflage.  Their mates, however, are dark brown, with a bit of white patterns that will make them invisible, which is especially beneficial when they are raising young in inland Canada.
     If on a sandy beach or by a rock jetty along the Atlantic Coast in winter, look for these birds in those habitats.  They will make a days on winter beaches more interesting.