MARINE SECRETS

New Zealand Herald, Volume LXXI, Issue 21717, 5 February 1934, Page 10

MARINE SECRETS

RESEARCH SHIP'S WORK STUDY OF WHALES' HABITS DAILY OBSERVATIONS TAKEN EQUIPMENT OF DISCOVERY 11. Scientific research of an advanced order under arduous conditions is the essence of life on the Royal research ship Discovery 11., which is now lying against Prince's Wharf while the crew enjoy a respite from the crowded days of work in the Antarctic seas.. To the unscientific observer her businesslike decks mean very little anc[ it is hard to realise that she is the finest research ship afloat. Every inch of her space has been planned following the experience gained in many .other ships of her kind. She differs from most of her predecessors in the comfortable quarters for her ship's company. It had been realised that her work necessitated almost continuous life aboard and that far better results would be possible by the provision of good working conditions. The broad idea of the work of the Discovery investigation is the study of the distribution of whales. The indiscriminate taking of the apparently unlimited supply of whales has caused the Government of the Falkland Islands concern as to the possibility of their extermination. For some years now a succession of research ships manned by crews well versed in a specialised form of navigation and staffed by scientists who are making a life's study of marine life, have worked quietly and efficiently in this most useful work. Diet ol Shrimps

The distribution of * the whales, is determined by a lone chain of causes and effects. The Antarctic whales feed on animals of the shrimp type and these feed on the "krill," a microscopic plant population. The distribution of the Icrill depends on many factors, the intensity of the light, the nutritive salts in the water, the depth of the ocean, the temperature of the water, and the presence of ice. Again, the whale population varies in the same place from year to year, both in density and, in the types of whale. Thus, successive observations have to be made in the same place.

At least once a day a complete set of data is collected. The ship is hove to and the scientific staff and their assistants from the crew take up their stations. Then, with a skill born of lone practice, the various sets of gear are adjusted to be sent overboard.

The daily observation is usually done at eight o'clock each evening. This is because the forms of sea life in which the expedition is most interested come nearer the surface by night and recede by day. Well-placed electric lights enable this work to go on without inconvenience.

The water sampling bottles are set on the lines to operate at different depths. The bottles are strong metal cylinders, which are sealed when inverted. When the whole series are in the desired position a weight is sent down the cable. On reaching the first bottle this turns it over, thus trapping a sample of sea water at that depth and fixing the thermometer that is inside the steel cylinder. At the same time there is released a second weight which travels on to the next cylinderto repeat the performance. This eoes on right down to the last bottle and the whole series is then slowly and carefully hauled to the surface! Samples of Marine Life

From the other stations of the ship nets are. lowered to different depths to take special samples of marine life. These nets vary from those of the finest silk, which are capable of trapping the most minute forms of life, to the nets of larger mesh, which take up the shrimp life which forms the actual feed of the whales. When necessary, other forma of lifa are taken as these hare a bearing, directly or indirectly, on the general distribution of the whales.

Another form of recording is that of the actual depth of the ocean. This is done by one of two special echo soundranging instruments operated from the bridge. Both rely on the echo from the bed of the ocean of a heavy hammer, which strikes the bottom of the ship with a loud metallic clang. Tho latest type actually draws a graph of the bed of the ocean at any required interval. The other is worked by an operator, who listens for the echo and works out the result from a large dial. Good work is also done by the Discovery 11. in actual additions and corrections to the existing charts. Many of the sub-Antarctic islands and their surrounding waters have been but imperfectly charted and at least a month on each commission is spent on this work alone.

The busy four hours just described form only part of the daily task. Each sample has to be carefully worked out from several angles. In one part of the fine laboratory two scientists are kept hard at work doing delicate tests of the sea water for its salt content and its temperature 'find density* Identified and Numbered . the other the net hauls are put into separate vessels and t>aeh form of marine life is identified and estimated as to numbor. When it is realised that as many as 20,000 are taken at a tame some idea of the task involved can bo imagined. Samples are bottled for future reference and numerous entries made on specially-prepared charts. Actually so much work must be done between one haul and the next that all members of the staff find little time on their hands. The essence of their life is hard, concentrated work of a highlytechnical order. All this is done under conditions that would be impossible for any but those used to the work. Microscopic work is particularly trying in a laboratorv that is never still. »

Apart from a most complete library, containing almost every scientific work written on work in the Polar seas, there is every conceivable form of equipment, and special provision has to ba made to allow for the long intervals away from tho sources of supply* Below decks are comfortable cabins for the accommodation of the crew where life goes on happily. On tho Discovery 11. one finds a proof of the maxim that the happiest people alive are the busiest.