NATURE NOTES

New Zealand Herald, Volume LXXI, Issue 21716, 3 February 1934, Page 1 (Supplement)

NATURE NOTES

BY J. MtUMMOND, F.L.S., F.Z.S.

THE RESTLESS SEA

The sea has played an important part in New Zealand's geological history. Several times it has completely submerged the country. By taking a large block of land, it now separates New Zealand by 1200 miles of water from the Australian continent, of which Old New Zealand was a part, leaving it a group of islands. Former connection with the continent stamps New Zealand as a continental island group, distinguished from oceanic islands, most of which are of volcanic origin, or were built upon coral reefs. For these reasons the sea and its power and importance in the world closely interest all who concern themselves with New Zealand's present and past affairs. Unconsciously, writers in our own times have expressed a view set out by the Preacher long ago in one of j the most beautiful books of the Old Testament. He searched into all things done under heaven and found no new thing under the sun. " All the rivers run into the sea, yet the sea is not full," he wrote; " unto the place from which the rivers come, thither they return again." A modern writer pays homage to the sea in similar words: " It is the destination to which most rivers and streams hasten; it is the ultimate source of all rivers and streams, which, without it, havo no separate existence." To another writer, it is the primary source, as well as the ultimate goal, of all rain, the great final reservoir of all water gathered by the earth upon its surface. Other tributes are paid to it as a highway over the earth that provides an unrivalled route of migration for all sorts and conditions of marine creatures ; as the greatest agent of destructive and constructive action; as the cradle of life, the earliest forms of living things, perhaps, having come from it; as the preserver of the remains of plants and creatures, which are records of contemporary life for hundreds of millions of years; as the most successful sculptor of the earth's surface; as thb most stupendous fact in the earth's long, eventful history. The sea's golden age was in the Cretaceous Period, the Age of Chalk. Deep calling to deep, it advanced, and the land trembled. All low-lying lands and all valleys near the continents' edges were swallowed up. These words are figurative. The advance was not sudden or tumultuous. Flowing and ebbing, and gaining continuallv, the sea seemed to feel that there was eternity in which to complete its victory. The recession of the waters that marked later epochs was not contemplated. Famous marine reptiles, whose remains rest in rocks in New Zealand and in many other parts, reached their greatest development in Cretaceous seas. Most of them became extinct about the time that the Cretaceous Period ended. Then, and later, there stretched across a large part of the world the vastest inland sea of which there are any traces. Extending east from the Atlantic through tho Mediterranean Basin, it covered the whole of Southern Europe and Northern Africa. The sun shone on it in Asia Minor, Arabia, Persia, Baluchistan, the Himalayan area and Further India. It girdled half the globe. Sway of battle between land and water changing, the Himalayas, the Caucasus and the mountains of Persia, Arabia, and Asia Minor usurped the eastern half of the Central Sea. The Carpathians, the Apennines, the Swiss Alps and the Pyrenees arose near its northern shores. It was broken up into disconnected inland seas and into salt water lakes. As the water continued to retreat, the Central Sea graduallv shrank. The Mediterranean Sea is all that remains of its glory.

Mr. A. H. Clark, an American oceanologist, has given in a single paragraph an account of some of the conditions in the deeps: " The temperature of the water declines as the depth increases. It declines rapidly at first, then more slowly. In the abysses it is mostly a few degrees above freezing point. The pressure increases. The light gradually fades. At about 650 ft. in the clearest and most sunlit seas there is only a pale moonlight at noon on the brightest day. At greater depths there is no light whatever. Wave motion dies away, and not far below the surface there is perpetual quiet even in the fiercest hurricane." A white harrier-hawk has attracted the attention of Mr. G. Smith, who is prospecting for gold on the Motatapu River, a tributary of the Matukituki, which flows into the south-western corner of Lake Wanaka. " Almost ©very day," he wrote in December, " I see a pure white hawk, usually accompanied by two hawks in ordinary plumage. I asked several people, including musterers, about it. They replied that it is the only white hawk they have seen. Are there any other white* hawks in New Zealand?" There are, but they are novelties. Some are complete albinos, like the hawk Mr. Smith refers to; others are partial albinos; others are merely hoary from age. Maori names for the mutants show that they were known of before Europeans came to New Zealand. The ordinary harrierhawk is kahu; a hoary individual is kahu-korako; a legendary white hawk, evidently an albino, is matakirea, Many years ago an albino was caught in a rat-trap in Christchurch. Except for a few brown feathers on the upper surface and for a tawny wash on the lower surface, it was snow-white. There was in Nelson Museum, and may bo there still, an albino har-rier-hawk shot at Riwaka, Nelson. It was a delicate white ash-colour, i+s lower surface tinged with rosy purple. Sir Walter Buller states that a taxidermist who was asked to set up this specimen felt that ho should charge a higher fee than usual for preparing such a handsome skin. Sir Walter Buller saw a perfect albino hovering over fern that fringes -the deep blue water of Lake Takitapu, between Lake Taupo and Lake Tarawera. As it descended to take .a rat or a lizard in the fern, its white plumage glistened. Forty years ago a hoary male hawk, very aged, was a feature of bird life on the lovely Pa pa i tonga Estate, sixty miles north of Wellington, bought by Sir Walter Bullor from the Ngatiraukawa owners. At noon one day a cry was raised, "The White Hawk!" Maoris and Europeans on the estate, rushing out, saw it fly over the lake to a bait of eels laid for it. Another hawk in ordinary plumage came out of the skies. They met face to face and fought in mid-air from one side of the lake to the other. A cadet, coining out with hia gun, found a party of twelve Maoris sitting on a slope watching the fight and backing the white hawk. It heard him when he was within forty yards, and was up at once, but a minute later a charge of quail-shot killed it without spoiling its plumage. I