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How do oystercatchers open shellfish to reach the flesh inside?

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Two wild horses graze on tall grass in the open prairie of Theodore Roosevelt National Park, with rolling badlands visible in the background. — Feeding behaviour Wild horses graze in the Badlands of North Dakota.

Oystercatchers are specialized shorebirds that feed primarily on mollusks, such as oysters, clams, and mussels. Their feeding behavior is adapted to the tidal cycle; they target their prey as the tide ebbs, when the shells are exposed and still partially open.1

To access the flesh inside, these birds utilize their unique, laterally flattened bills, which feature tips that form a vertical blade. This structural adaptation allows the oystercatcher to insert its bill into the gap of a partially open shell to reach and consume the soft tissue within.21