The American Avocet
American avocet (Recurvirostra americanas) is an extreme feeding specialist among shorebirds. Its long, slender bill turn up at the end and is often used to sweep the water just below the surface, setting up minute currents that waft small creatures between the mandibles.
This feeding method is called “scything”, and it works most efficiently when the birds move “line-abreast”, each one stirring up the prey for its neighbors so that they feed more efficiently in a flock than they would alone.
Avocets eat aquatic invertebrates, including worms, beetles, water boatmen (named for their flat, boat-shaped bodies and long, fringed, oar-like hindlegs), brine flies, fairy shrimp, water fleas, and amphopods (a crustacean that is shrimp-like in form). They also take small fish and the seeds of aquatic plants.
Though they usually feed while wading, avocets can swim, and upend like ducks to capture prey in water too deep for wading.
While I have never witnessed the avocets feeding in a line, I have seen them swimming in the Mitigation Ponds. Others have seen them feeding solo in the channels coming into the Park, or on the upper Wash (above the Clark County Reclamation Facility). I think that is what attracted me to write this Nature Moment; I had never thought that feeding in a line would be more efficient than having all the food to yourself! If any of you have seen “scything” in action, we would appreciate a reply to this post! – Chris Leavitt, President