Fish
A fish is a vertebrate animal. Nearly all ofthem are ectothermic, which means 'cold-blooded'. Fish generally have two sets of paired fins and several unpaired fins. Their bodies are covered with scales, and they need to be able to cope with the pressure of the water around and above them.
Some fish that live in pitch black conditions in very deep water, are able to withstand the immense pressure of the water above them. Some recent research appears to indicate that there are a huge number of species of fish living in very deep water, in pitch black and designed to withstand the immense pressure of the water!
 glowlight tetra © Copyright JoJan Creative Commons Licence  |
 tiger shark © Copyright Terry Goss Creative Commons Licence |
Fish are abundant in all the oceans, seas, rivers and lakes, except the dead sea! There are other waters which have been polluted by man's activities and where all the fish have been killed off!.
Fish are important as food for people throughout the world. Overfishing in certain areas of the oceans have depleted fish stocks to the point where it is no longer commercially viable to fish there.
 grouper © Copyright Craig Pemberton Creative Commons Licence |
 striped bass © Copyright Stevenj Creative Commons Licence |
Fish farming provides supplies of fish, such as salmon and trout for the retail trade. Fish farms operat in both fresh water and sea water.
Fishing is a major recreational hobby for many people. Course water fishing takes place in fresh water lakes and rivers, and it is usual to put any fish caught back in the water.
In sea angling, a popular hobby, the fish are not put back!