PIED AND BLACK OYSTER-CATCHERS.

Forest and Bird, Issue 49, 1 August 1938, Page 7

PIED AND BLACK OYSTER-CATCHERS.

(By L. W. McCaskill.)

Black Oyster-Catcher (Haematopus unicolor).

Pied Oyster-Catcher (Haematopus longirostris).

Although the Pied Oyster-Catcher and the Black Oyster-Catcher are different species, their habits are somewhat similar and in some parts of their range, especially in the North Island, they interbreed. In the southern part of the South Island the two species associate on the coasts in the off-season, but for nesting places the black species seeks such rocky coasts as the West Coast Sounds, while the pied species may go far up the snow rivers and even into the mountains. Many people know them as Redbills; others use this name for the Red-billed Gull, an entirely different bird. The Maori name for the Pied Oyster-Catcher is Torea, for the black one Torea-pango. During the autumn and winter months the birds are usually seen along the coasts and tidal estuaries. They form an attractive picture sedately reposing on the sand, occasionally uttering a shrill pipe, or running to and fro searching for food left by the receding tide. Unless they are separated by a stretch of water from the observer, the birds appear wary and restless. Each bird seems always ready to rouse the rest with its clamorous alarm note. When feeding, some may be seen dislodging small shellfish such as limpets from the rocks — more frequently they probe in the soft wet sand or mud for marine worms and various crustaceans. Sometimes they search for food among the seaweed in rock pools. Some birds nest in the sand dunes or on a rocky island off shore. Many leave in the late winter for the inland river-beds. Here on a sand-spit or bank of shingle, a small hollow suffices for the nest. Oyster-Catchers dislike dense shelter near the nest, and for this reason it is feared that the spread of gorse, lupin, and similar weeds on the river-beds is reducing the area available for nesting sites. When preparing to nest the male bird has been described as “paying his addresses to the mate of his choice; elevating his back and lowering his bill until it nearly touches the ground; strutting or running round her with a loud quivering note, no doubt expressive of his undying attachment.” The colour, shape, and markings of the two or three eggs vary considerably, but in all cases

the protective colouration enables them to harmonise effectively with their surroundings. The young are able to run shortly after they are hatched. Soon they accompany their parents on their foraging expeditions, prying into every crevice in search of insects and their larvae. The adult has a wonderful capacity for taking care of the young. At a note of warning from the watchful parent, the young birds will crouch motionless, their protective colour and markings blending with the surroundings to make them almost invisible. At the same time the adult bird will attempt to lead away the intruder by feigning lameness, appearing to be suddenly crippled in the wings or by toppling over. The Maoris believed that the Torea-pango know of an approaching storm which it indicated in note, crying “Keria, Keria,” before a storm, and “Tokia, Tokia” after one.