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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.

During the period 20–21 December 1972 while travelling from Wellington, New Zealand, to Hallett Station, Antarctica, observations were made on the spatial distribution of Adelie penguin age groups. It was found that during this period one-year-old birds were found at a noticeably greater distance from an established breeding rookery than were the birds two years old or older.

Displays observed at sea for four species of albatross (Diomedea exulans, D. melanophris, D. cauta and D. chlororhynchus) off the south-west coast of South Africa are described. Incidence of occurrence is related to time of year and to number of birds. Displays were observed mainly in November and December, during the breeding seasons of all four species. It is suggested that displays at sea occur among non-breeding adult and immature birds and are similar to pair-formation displays at the breeding grounds.