An apparently new sandpiper species ("Cooper's sandpiper Tringa/Calidris cooperi") was described in 1858 based on a specimen collected in 1833 on Long Island, New York.
Putative hybrids between the dunlin ("Calidris" alpina) and the white-rumped sandpiper ("Calidris" fuscicollis) have been occasionally seen in northeastern North America [REF].