NATURE NOTES

Evening Post, Volume CXIX, Issue 98, 27 April 1935, Page 17

NATURE NOTES

BIRDS ON THE HARBOUR

THE TERNS

(By R. H. D. Stidolph,. R.A.O.U.V

The distinction of being the nibs', graceful bird around the New Zealand coast can be claimed by the whitefronted tern or black-cap, as some people call it. Most terns have black caps, however, and this name is not sufficient to avoid confusion between the different species. Another common name applied to the white-fronted tern is that of sea-swallow, no doubt an allusion to its supposed resemblanca to the Old World swallow. The natur» alist prefers to know it as the whitefronted tern, on account of its forehead being white and thus separating the black crown from the black bill. The wings and back arc a delicate shade of grey and the underparts pure White. New Zealand shares its possession with the eastern parts of Australia and with Tasmania. It is nearly always to be seen on Wellington Harbour and at times is quite numerous. Its presence is usually denoted by its : sharp cry of "kek," uttered at intervals during its fishing excursions and then, perhaps, the bird, itself may be ' seen to drop into the water and reappear with a small silvery fish in its bill. :•. ■ . ,-.■■..' ■ , •/.. :'; The tern retires to a lonely rock or tq some isolated spit on which to rear its family. On a rock little or no ■ attempt is made at nest building. Perhapfc a few small round stones are placed together so as to form the rudest form of a cradle or perhaps the egg is merely deposited on the rock, apparently without any preparation in: the way of a nursery. In other localities some pretence of a nest of modest structure is occasionally to be seen, but generally speaking, the bird is not greatly concerned with work of this kind and is content to use any piece of rock or beach that provides at least some degree of comfort. The eggs of the white-fronted tern vary greatly in colour but usually are of a greenish stone, heavily blotched with sepia and underlying marks of dull grey. It seldom lays more than a single egg but sometimes a more prolific bird, has two in a clutch. The young birds are pretty little creatures, clothed in a light-coloured down, mottled on the back with grey. The adults are most courageous, and swoop downwards with an angry snapping of their bills, showing defiance at the approach of human intruders to their breeding haunts. Fortunately, this beautiful bird is quite abundant around the New Zealand coast. Several other species of terns ars found in New Zealand waters, but the only one, in: addition to the ■whitefronted tern, to be seep regularly on the waters of Port Nicholson is the largest and one of almost cosmopolitan distribution, a species known as the Caspian tern. It is more in evidence during the winter months,, especially near the mouth of the Hutt River, but is sometimes to be seen even, in Oriental Bay and in other parts of the harbour. The Caspian tern is easily recognised by its large size and stronglooking scarlet bill, which is usually pointed downward when the bird is in flight. Like other members of the family, the Caspian tern is an expert in the art of fishing and on account of its larger size it has a' more varied bill of fare. It is nowhere very numerous, although it is well distributed all around the New Zealand-coast in suitable localities. It has. a preference for the mouths of rivers and for the quiet reaches of land-locked harbours, and occasionally it pays a visit to lakes or lagoons adjacent to the sea. It is, however, a coastal bird, although in tho breeding season it may sometimes select a site for its nest on a shingly riverbed at some, considerable distanca from the sea. ' Among the terns inhabiting New Zealand is the black-fronted species, an exclusive possession of this country. It closely resembles the white-fronted bird but lacks the white forehead arid black bill, the black on the crown ol the head extending right down to the bill, which is orange in colour. The black-fronted tern frequents districts adjacent to the sea as well as the coast. It oftens follows the plough in search of grubs and worms and is ; a good friend of the farmer. The black- • fronted tern is more numerous in-Can-terbury than elsewhere and apparently it is not known to breed beyond that district. Its breeding haunts there are the extensive riverbeds, where the bird is still present in fairly large numbers. Elsewhere, however, it is almost unknown, and it is quite an event for the bird to turn up in the North Island. Even in other, parts of the South Island the black-fronted tern' is seldom met with. Exactly why it should be so restricted in its distribution 1* hard to understand, as there are shing^i* riverbeds in the Wairarapa and Maiii* watu districts that appear to afford a* mirable breeSihg-localities. - In anf case, although its numbers have certtainly decreased, it seems to be thrxv* ing fairly well in spite of the change* that have, taken place. - V The rarest of New Zealand terns is the smallest, a species known as the little tern. It is very much like the familiar white-fronted tern except that it is smaller, of course, and has the bill an orange-yellow, instead of black. Very few authentic records of its occurrence on our coast have.been noted, and it appears that it is a decidedly rare bird in New Zealand, unless it is overlooked by the ordinary observer or confused with other ■' species. It has been recorded, away back in 1869, as breeding on the Rakaia riverbed in Canterbury, many miles inland, and according to all accounts, is more numerous in Canterbury and Marlborough than elsewhere in New Zealand. Many years ago the late Sir Walter Buller records Seeing a pair on Papaitonga Lake, near Levin, but this bird is only encountered at long intervals in the Wellington district. Like the' blackfronted tern, however, it is'abird that may turn up on Wellington Harbour almost any time, especially in the autumn and winter months, so that a bird-lover may never know when he may find a visitor of some interest on the waters of Port Nicholson.