Can fish hear fishermen moving along the stream? What are the facts about the ability of a fish to see?Can they tell the difference between colours?
The sharp hearing of a fish has been proved by two scientists.These men trained a fish to expect its food when it heard the sound of a whistle.The fish always opened and closed its mouth when it heard the feeding signal .And it was also proved that even a slight sound two hundred feet away could drive them away.That should make fishermen start thinking!
One scientist has made more than fourteen thousand experiments testing the ability of fish to recognize different colours .A small bottle with a coloured sign round it was lowered among the fish.When a fish swam near it .The food was given .Then other colours were wrapped round the bottle.If a fish came near these,a gentle electric shock was given as a punishment by touching the fish's back with an electric wire.After between five to ten times,most of the fish could tell the difference between red ,brown ,yellow and green.
Fish also have an eye for different shapes.One of the experts in the field proved this by teaching fish to connect certain patterns with food.He used a small circle and a square.If the fish swam towards the circle,, they received food as a reward.If they swam towards the square,they received nothing,The fish learned in time to go to the circle but not to the square.Does this mean that in time fish might learn to leave alone all food on hooks that they have seen often before?Here is something for all fishermen to think about.
These facts help to make more believable some of the "believe it or not " stories that have been told about fish .It is clear that fish have sometimes shown their ability to gain knowledge as man does.
It was reported once there was a pool of goldfish with a little platform above it .The platform was covered at certain times with plenty of ants' eggs, and tied up by a piece of string. The end of the string hung in the water.The goldfish quickly learned how to feed themselves by giving the string a pull ,Pulling this string turned over the platform.At once a shower of ants' eggs would fall into the water.
A good example of what we might call "thinking" by a fish is given by an experience of Dr.Andrew Gage.Fishing over a bridge he hooked a fish .It struggled and dragged the line two hundred feet away before he stopped it .Thenit swam back towards the bridge.The clever fish then swam round a pile and , with a sudden pull,broke the line.
If the story ended there,one could say that the fish had freed itself by chance.However,Gage went on fishing.Below his he could see the fish that had broken loose.After another twenty minutse the fish again seized the food on the hook.This time it did not swim out .It swam round one of the piles under the bridge and again broke the line.
Many stories are told of the fishes that get away and the clever "old hand" ones that cannot be caught.Fish seem to learn by their own experience.The more often a fish is nearly caught.the more difficult it will be to interest it next time.