lem in the world. In 1964, the world fish catch contained 17.1 billion 
pounds of protein (based on wet weight of fish containing 15 percent 
protein), an amount which would have supplied slightly more than 
10 grams of protein per day to 2 billion individuals, and would have 
been effective in eliminating or alleviating chronic protein deficiency 
for the people of the equatorial zones. That this opportunity for up- 
grading nutrition has not been adequately exploited, reflects cultural 
as well as economic barriers, failure of distribution, and inefficiencies 
of use. 
2.2. PROTEIN PRODUCTION IN THE SEA 
It is estimated that at least 400 billion tons of organic material, 
wet weight, are produced annually in the sea, only a tiny fraction of 
which is harvested by man. In the sea, as on land, food is produced by 
plants that utilize energy in sunlight to synthesize organic materials 
from inorganic substances. The “grass” of the sea, composed of mi- 
croscopic plants (phytoplankton) is eaten by the grazers (zoo- 
plankton) which in turn are consumed by larger animals such as 
fish. This isthe food chain of the sea (see sec. 6.4). 
Agriculture to be highly productive requires continual replenish- 
ment of plant nutrients through artificial fertilization. In the ocean, 
nutrients are replenished by natural processes such as regeneration due 
to microbial activities and inflow of fresh waters which contain nu- 
trients from the land including agricultural fertilizers and sewage. 
With the death of animal and plantlife in the sea, the organisms sink 
- and are decomposed, releasing nutrients. These nutrients are concen- 
trated in bottom waters where, due to the absence of light, they cannot 
be used for photosynthesis. In areas of upwelling, the nutrient-rich 
bottom waters are brought to the surface where they sustain large 
populations of phytoplankton. Wherever this occurs, such as in the 
Humboldt current off the coast of Peru, phytoplankton flourish and 
a vigorous food chain is sustained, leading to the production of large 
quantities of fish. 
2.3. THE WORLD FISH CATCH 
The present world fish catch is about 114 billion pounds (table 2.2). 
The magnitude of the catch is dependent upon many factors, among 
which are the rate of production of fish in a given area and intensity 
of harvest. These factors vary for different species and for different 
areas of the ocean. The catch increased from 60.5 billion to 114 bil- 
lion pounds in the last 10 years. It is uncertain how large a crop can 
be harvested. The most dramatic instances of increased catches in 
recent years have resulted from finding new fishery stocks. Indeed, 
the most dramatic has been off the coast of Peru, where a catch of 20 
c 
