Problem

Threatened species of Pisces


Experimental visualization of narrower problems
Other Names:
Fish at risk of extinction
Endangered species of fish
Nature:

Due primarily to the impact of man on the natural environment, whether directly of indirectly, many of the 23,000 species of fish are in danger of extinction. Technological 'advances' have enabled the total world catch to increase by a factor of 70 over the last two centuries. Of that which is caught only 71% is considered fit for human consumption. The rest is fed to pigs and chickens, made into pet food, or used as fertilizer. Sharp drops in fish stocks can be related to changes in ocean currents and other natural phenomena that fishing fleets often do not take into account. Intense exploitation during a period of current-caused low productivity can deplete a fishery.

Incidence:

With reference to particular species: (1) It is known that the Atlantic salmon has been hunted to the verge of extinction. In 1967, the catch in estuaries, spawning rivers, and oceanic home waters was almost 10,500 tonnes. In 1982, with many more sporting hunters and much more efficient commercial fishing, the catch declined by 40%, to 6,100 tons. In 1984, spawning runs in Canadian rivers were reported down more than 50% from 1982. The Newfoundland commercial catch dropped to barely half that of three years ago. (2) The California sardine fishery, which hit its peak of 1,500 million lbs (670 million kgs) in 1936, ceased to exist by 1962. Sardines also practically vanished from such hitherto productive areas as Brittany, Portugal, and Morocco. (3) Anchovies caught by Peruvian fishing boats in the Humboldt current are processed into fishmeal for export. Livestock throughout the world, especially chickens and pigs, are raised on this meal. Shifts in this current, coupled with overfishing, have drastically reduced the Peruvian anchovy fishery, which once made Peru the world's largest fishing nation.

Problem Type:
A: Abstract Fundamental Problems
Date of last update
14.06.2018 – 06:42 CEST