Avocets and Stilts

     About a half dozen American avocets have recently been feeding on invertebrates on the Conejohela Mud Flats in the Susquehanna River in Lancaster County, Pennsylvania.  These birds raise young around lakes and ponds in the American prairie pothole region, but some post-breeding avocets wander east to the Atlantic coast and feed, individually or in small groups, in marshes and shallow impoundments.  And some individuals, such as those at Conejohela, feed from large inland flats and shallows, exciting eastern birders and non-birders alike. 
     American avocets have long, blue-gray legs, lengthy necks and beaks, white bodies, black stripes on wings and backs, and light brown on their heads and necks during the breeding season.  There are a few other kinds of avocets in the world's wetlands and several kinds of stilts, all of them together making the family of birds called Recurvirostridae.  Birds of each genus live on all continents, except Antarctica. 
     Black-necked stilts live and breed along the southern parts of the Atlantic and Pacific coasts and the Gulf Coast of the United States.  They have long, red legs, lengthy necks and bills, and are black on top and white below.  This kind of stilt has also been spotted occasionally on flats and shallows on inland retention basins and other shallow water impoundments.      
     Because they are related to each other, all species of avocets and stilts have characteristics in common.  Both genders of all species are alike.  Each bird has one mate to raise young with each year.  Each female lays four eggs in her nest on the ground, as most shorebirds do.  Every pair of each species shares the work of raising the young.  The chicks are downy, open-eyed and ready to run and get their own food within 24 hours of hatching.  Parents brood the chicks during inclement weather and warn them of danger. 
     Each genus of birds uses its long legs to wade in water and their lengthy necks and beaks to snare prey animals, which includes aquatic insect larvae, tiny crustacea, segmented worms, tadpoles and small fish.  But the different kinds of birds in each genus are obliged to bend over to get their beaks into the water for feeding.
     Avocets and stilts have differences that reduce competition for food between them.  All species of avocets have thin beaks that curve up near the tips.  They sweep those bills from side to side in shallow water and grab and swallow any small critter their bills bump.
     The slender bills of all stilt species are straight and they use them to pick up tiny prey species from the surfaces of water and mud in shallows and flats.  They feed by rapid dabbing.  
     Avocet and stilt species through the world are uniquely built for how they get food, making them unique, and interesting to us.  American avocets and black-necked stilts are the only kinds of their family that dwell in the United States.  When along shallows and mud flats by the coast, or inland, late in summer and into autumn, one might see a few of these intriguing kinds of long-legged, long-necked birds.