Appearance The black oystercatcher is a distinctive, crow-sized, short-tailed, all-black shorebird. It has pale pinkish legs and a long, bright reddish-orange bill and eye-ring. Within Alaska , they have ranged northward to the Pribilof Islands in winter and to Round Island , Bristol Bay , to nest in the summer.
It is a permanent resident on all five islands in the park. Ranges of the black oystercatcher and the brown-and-white American oystercatcher overlap in Baja California. Habitat Oystercatchers never stray far from shore and favor rocky shorelines in particular. Feeding Mussels and limpets are their primary food, but black oystercatchers prey on a wide range of shellfish and other creatures found along the rocky shore.
They locate open mussels and disable them with a quick jab to the adductor muscle. With the mussel stuck in the open position, the oystercatcher can pull out the contents with the tip of its chisel-like bill. Oystercatchers often forage in the wave zone, because mussels that are splashed by waves open more frequently.
Reproduction The female black oystercatcher lays two to three eggs among pebbles in a shallow rocky depression or in a hollow on the beach above the high tide line. The nest is built by both the male and the female. Video lessons. Teacher development. Teacher programs. Project-based science examples. Book a field trip. Online courses for teens.
Teen programs. Teen career resources. See all courses. Learn more and sign up. Search through the site content. Enlarge image. Animal type Birds. Size Up to Diet Intertidal marine invertebrates, such as bivalves, limpets, whelks and chitons.
Relatives Other black oystercatchers. Natural history. Related Video. Cool facts. Monogamous pairs make their nests by tossing rock flakes, pebbles or shell fragments toward their nest bowl with a sideways or backward flip of their bills.
They use the same nest year after year. Limpets and mussels have a strong muscle that holds the two shells tightly together — yet an oystercatcher can easily and quickly pry them open. The birds also sneak up on open mussels, quickly stab their beaks between the shells, sever the muscle, shake it free and swallow it.
With sharp jabs of their bill tips, oystercatchers dislodge limpets and chitons from rocks. Then they turn the molluscs over and eat the soft tissue. Peek into our Aviary for an adventure in birdwatching. Watch the live cam. Read about how the Aquarium is getting involved in protecting wild penguin populations.
Meet our penguins. See more. Download a beautiful, high-resolution snowy plover wallpaper for your desktop or mobile device. See wallpaper. Individuals have two main techniques for handling their difficult prey. Some, which have shorter, blunter bills, specialise in hammering the prey through the shell.
Others, with longer, pointier bills, prise the two shells apart. The longevity record for an oystercatcher stands at 40 years, one month and two days.
Ringed as a chick in , it was last caught by a bird ringer near the same place on the Wash in Lincolnshire in While black oystercatchers are a designated as a Species of Least Concern by the International Union for Conservation of Nature IUCN , their populations in some areas are declining, primarily due to human disturbances along shared shorelines, hazards such as oil spills, pollution, and loss of habitat. The presence of oystercatchers is a sign that a coastline supports abundant mollusk-type invertebrates and is a flourishing, healthy environment.
When we work to protect black oystercatchers, our coastal areas—in the northern Pacific and even along the shorelines of Puget Sound—will thrive too! Oystercatchers nest and spend winters in the same basic area. They make nests near rocky tidal areas where food abounds. By flipping their bills sideways and backwards, the birds toss rock flakes, pebbles and shell fragments to create a nest that resembles a bowl. Each pair will raise a clutch of eggs one to three eggs at a time.
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