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New Zealand oystercatchers use specialised prey-specific methods to feed on common prey found in the marine littoral zone. Methods of locating and dealing with bivalves, limpets, chitons, gastropods, and crabs are herein described. Feeding behaviour may be modified by climatic factors, physical factors of the environment, and competition for food. The mainland species of oystercatchers have similar repertoires of feeding methods, but the South Island pied oystercatcher is behaviourally adapted to exploit estuarine bivalves whereas the variable oystercatcher is adaptively superior in exploiting limpets and chitons on rocky shores. The Chatham Islands oystercatcher seems behaviourally intermediate to its mainland congeners in feeding habits, possibly in response to widely varying feeding habitats in the islands. Differential niche utilization may therefore have been an important factor in the speciation of New Zealand oystercatchers.