[Mystery bird] American Avocet, also known as the Blueshank, Recurvirostra americana, photographed at Bolivar Flats Shorebird Sanctuary, Houston, Texas. [I will identify this bird for you in 48 hours]
Image: Joseph Kennedy, 6 June 2007 [larger view].
Nikon D200, Kowa 883 telescope with TSN-PZ camera eyepiece 1/640s f/8.0 at 500.0mm iso400.
Please name at least one field mark that supports your identification.
This bird has a peculiarly-shaped beak.
- Can you tell me the technical (ornithological) term that describes this bird’s beak shape?
- What does this bird’s beak shape tell you about its feeding behaviors?
- Does this beak shape tell you what sort of diet this bird has?
- Can you name any other bird species that have a similar upward curving beak shape?
An upward-curving bill is referred to as “recurved.”
Avocets use two feeding methods. In clear water, avocets wade into water and feed by sight by picking prey from the surface of water or mud, using its long, thin beak like tweezers. In poor visibility and when locating prey from within the sediments, they forage by touch, sweeping the long, upcurved bill from side to side through water or loose sediment to locate hidden prey.
In deeper water, avocets swim and up-end like a duck to reach food below the surface. At times large feeding flocks will assemble to feed cooperatively on animals such as shrimps on the edge of a rising tide.
The primary food is invertebrates, especially crustaceans and worms. In fresh water they also take insects found on the surface or within the top layers of the bottom sediments.
Three congeners; Pied Avocet, Recurvirostra avosetta, Red-necked Avocet, Recurvirostra novaehollandiae, and the Andean Avocet, Recurvirostra andina. Another shorebird; Terek Sandpiper, Xenus cinereus, and a passerine, the Recurve-billed Bushbird, Clytoctantes alixii.