OCEANOGRAPHY AND THE MARINER 



the compacted and less porous buried deposits, and the bedrock. 

 Much work is needed in this area for the improvement of degaus- 

 sing techniques, sonar utihzation, and minesweeping. 



Marine geologists and geophysists conduct many other phases 

 of oceanographic research, most of which do not directly concern the 

 mariner. By studying the history of our planet as revealed by sedi- 

 mentary deposits and bottom topography, man is enabled to further 

 understand the history of the universe. Millions of years of erosive 

 activity on land have deposited unknown and untapped amounts of 

 mineral resources in the sea. These deposits become increasingly 

 important as our present natural resources are slowly exhausted. 

 Precise navigation, improved echo sounders, bottom photography, 

 acoustical probes, and long coring tubes have all aided in locating 

 and charting many areas having potential mineral reserves. Today, 

 large quantities of oil and sulphur are obtained from beneath the sea 

 floor. Magnesium, bromide, iodine, and a few other elements are 

 extracted in smaller quantities from sea water. 



BIOLOGY 



It has been estimated that at least a million vessels of various 

 sizes, and about four million men are engaged in some phase of the 

 marine fisheries industry. Of importance to this industry is that 

 phase of oceanography dealing with marine biology. 



The endless search for did and new forms of life in the oceans 

 has attracted freshwater biologists as well as marine biologists. 

 These scientists probing in the many divisions of marine biology are 

 constantly striving to discover and classify the numerous marine 

 organisms and to clarify the ecological structure of the communities 

 which they form. Working hand in hand, the taxonomists, ecologists, 

 geneticists, biochemists, physiologists, evolutionists, and students 

 of animal behavior are undertaking research problems which con- 

 tribute to our overall knowledge of the life cycle of the sea. 



These scientists are attracted to the study of marine life mainly 

 by the unique research opportunities to be found in this field. 

 Animals living in a liquid world, eating and breathing in a manner 

 not too dissimilar to that of man but living under entirely different 

 environmental conditions foreign to and impossible for man, are the 

 basis for the never-ending research of marine biologists. 



The possible variety of environmental conditions under which 

 the sea creatures exist are countless and include extreme variations 

 of temperature, pressure, salinity, light, nutrients, weather, and 

 currents. Of these, the distribution of vital nutrients is probably 

 the most important controlling factor in the ups and downs of the 

 commercial fishing industry. 



The study of the relationships of organisms to environment is 

 known as Ecology. Much is known about these relationships, how- 

 ever, much more research regarding temporal and spatial distribution 

 of nutrients and animals is necessary if we are to make more extensive , 

 consistent, and complete charts of the ocean's communities. For- 

 mulation of such charts will require large-scale international coopera- 

 tion. Simple observational methods of the past will not achieve 

 our end; prior research must be performed, particularly in the 

 solution of adequate technical sampling methods, both instrumental 

 and statistical. 



The sea is considered an inexhaustible source of animal protein. 

 However, of the thousands upon thousands of species of animal life 

 contained therein, only about 300 species of fish and shellfish are 

 marketed by American fishermen. Sixty percent of the total annual 

 catch is composed of only 9 species, indicating the specialization in a 

 minority of what is actually available. 



Much study has been conducted by biologists, physiologists, 

 and students of animal behavior in determining the response of 

 various marine organisms to applied artificial stimuli, especially 

 electromagnetic waves of heat, sound, and light. The nervous 

 system of a fish regulates its muscular response and can be controlled 

 by application of variable-frequency electric stimuli. Pure AC 

 electricity has been used successfully in whaling operations; undula- 

 ting current has proven efficient for capturing small fish. Fish 

 attracted by underwater light can be pumped aboard by suction 

 hoses. What new methods are awaiting discovery through basic 

 and applied research? 



Worldwide surveys leading to complete oceanographic charts 

 will pave the way to better fishing methods by enabling us to predict 

 the times and places where fish will concentrate. They will also 

 provide an understanding of the ecological relationships between the 



animals and the stimuli of their environment. Knowledge of prey, 

 predators, competitors, and diseases will provide us with the key to 

 increasing the number and possibly the size of fish in the sea. The 

 prey, being the food source of the various animals, is the most 

 important of the foregoing factors, but as yet little is known about 

 it in spite of the amount of research already performed. Little is 

 known regarding the distribution of plankton, i.e., organisms at the 

 mercy of the currents. Why are the apparent numbers and eventual 

 sizes of plankton in polar seas so much greater than those of plankton 

 in warmer seas? What determines the discrete, regular distribution 

 of plankton though they are at the mercy of the currents? What 

 determines the balance between the size and numbers of zooplankton 

 and phytoplankton ? Open-sea waters are considered homogeneous 

 when compared with waters of the intertidal zone, yet plankton seem 

 to be more prolific in the latter environment. The phenomena of 

 "red tide" in the Gulf of Mexico and "El Nino", a warm current 

 counter to the Peru Coastal Current, are both only temporary 

 occurrences, yet each exerts a disastrous effect on the biological 

 communities in those areas. The "red tide" virtually suffocates fish 

 by the millions, while useless organisms thrive. Beachside human 

 communities suffer the aftereffects of these dead fish. Though much 

 research has been performed on the "red tide", no cure has been 

 found for the condition. "El Nino" has been studied less, but the 

 effects are the same with the exception that a side-effect, known as 

 "Callao painter", is the production of hydrogen sulfide in sufficient 

 quantity to blacken the paint of entire ships. How many more 

 similar undesirable conditions exist unknown in the oceans? 



Lower half of photo shows preventive effect of antifouling 

 paint applied to metat submersed for period of one year 



Another important phase of marine biology which affects all 

 ships sailing in both fresh and saline waters is the problem of foul- 

 ing. Attachment, entanglement, and boring organisms and corro- 

 sion have long been the scourge of the mariner. Clogging of sea 

 chests and intake lines can lead to serious damage to other major 

 machinery and result in costly repairs. Fouling growth in lines can 

 effectively reduce heat transfer in condenser operations. Accumu- 

 lation of attachment fouling organisms on underwater portions of 

 hulls can effectively reduce ships' speed. 



Fouling also produces adverse conditions for the operation of 

 underwater sound equipment. All forms of marine life, whether 

 attached, free-swimming, or drifting reduce the efficiency of under- 

 water sound transmission by interfering with the normal path 

 of sound waves. Air bubbles entrapped by attachment fouHng 

 organisms on sound domes and transducer plates can reduce sound 

 transmission by 30 percent, at the same time reducing echo intensity 

 by a factor of one half. The importance of such effects can be seen 

 in the application of sonar and fathometer equipment. 



