Oystercatchers (Haematopodidae)
ORDER
The sandpipers, plovers, auks, predatory skuas, and oystercatchers are just five of the nineteen families in the taxonomic order CHARADRIIFORMES (pronounced kah-RAH-dree-ih-FOR-meez).
FAMILY TAXONOMY
The Haematopodidae (pronounced hee-muh-toh-POD-uh-dee) family is composed of eleven species of oystercatchers in one genus distributed on coastlines of all continents except for Antarctica.
NORTH AMERICA
There are three species of oystercatcher sharing the same genus in North America. These include the American Oystercatcher, the Black Oystercatcher, and the Eurasian Oystercatcher.
KNOWN FOR
The American Oystercatcher, like other members of its family, is mostly known for its distinctive, orange bill used to pry open the shells of oysters and mussels.
PHYSICAL
Stout, medium sized birds, oystercatchers have rather plump bodies with thick necks, rounded heads, and medium length, pointed wings. They have medium length, strong legs and a long, straight, laterally compressed bill.
COLORATION
Oystercatchers are colored in a combination of black, white, light pink, yellow, and reddish-orange. Plumage of some species is black above with white in the wings and on the underparts, other species with all black plumage. The legs of all species are pale pink, the eyes glaring yellow, and the eye ring and bill reddish-orange.
GEOGRAPHIC HABITAT
This family is restricted to both coasts in North America, the Black Oystercatcher ranging from California to Alaska, and the American Oystercatcher occurring along the shores of the Gulf of Mexico and the Atlantic Ocean north to Maine. The third species, the Eurasian Oystercatcher, is an accidental vagrant.
MIGRATION
Most populations of oystercatchers are resident, the northernmost birds making short distance migrations.
HABITS
Oystercatchers are solitary birds only occasionally seen in flocks after breeding. They prefer to forage on rocky coastlines that provide habitat for their main food source; bivalve mollusks. Their strong legs and toes are suited to maneuvering on and gripping rocky areas favored by mollusks. Upon finding a mollusk such as an oyster, clams or mussel, they use their specialized bills to open them by inserting the bill to cut muscles that keep the shells tighly closed together.
CONSERVATION
Oystercatchers are not endangered in North America. In New Zealand, however, the Chatham Island Oystercatcher has a population size of just a few hundred and is endangered by introduced predators, while one species (or subspecies) of oystercatcher has gone extinct in the Canary Islands.
INTERESTING FACTS
The American Oystercatcher places bits of broken shells in its nest to help conceal the eggs. Both sexes incubate the eggs and are sexually dimorphic with females being larger than males. This difference in size helps them avoid competition by utilizing different prey items.