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Can Fish See And Hear?
We did a lot of fishing when I was growing up and having a lot of time to contemplate all things fishy brought me to asking a lot of questions, the first of which was:
Can Fish See And Hear?
Fish can see, although probably only when they are in water. There is considerable difference of opinion among scientists as to how well fish can see.
Their pupils are very large, probably to let in as much as possible of the faint light which filters down through the water.
Some scientists believe that fish can tell the difference between various colors. I'm not so sure about that, because I swear years and years of experience has taught me that if you make a lot of noise or sometimes any noise -- your odds of catching fish is limited.
It's still not known how well fish can hear, and many scientists believe that their hearing is limited to detecting sound-waves in water. At any rate we do know that fish have no outer ears. However, they do have a system of hearing through vibration.
Does A Fish Feel?
Similarly, as one of the family "official" fish cleaners after catch, this was a question upon my young mind that weighed heavily.
Certainly everything that lives, from a microbe up to a man, has some kind of feeling. The power to feel and to respond to what is felt a mark of all living matter everywhere. Its disappearance without return is the mark of death.
However, the amount and the quality and the clearness of feeling differ widely in various living things. So it would be wrong to say that a fish has no feeling; yet it does not feel as we do.
Seeing and hearing and touch are feelings of sorts. The fish can see and hear and touch.
However, they cannot translate much of what they see and hear and touch into meaning, at least in terms of how it is for humans. This is all because a fish has a simple brain. It is thought that a fish cannot feel pain as sharply as we do, even as some animals do.
How Fast Is A Fish Able To Swim?
In the past very few investigations were made to decide this question, but a Belgian scientist timed a number of salmon and concluded that they can swim a short way at the rate of about ten yards a second, or about as fast as a good sprinter can run.
Another scientist, an American, found that a fish called the "alewife" can swim at about the same rate as the swift salmon.
It is probably, however, that many fish can swim much faster than these figures of the past show. Sharks often accompany swift ships for days, and even porpoises can keep up with a big ship for a long time. Black marlins have been recorded at swimming more than 80 mph. It's by measuring how fast a fish caught on a reel and fishing line comes off that line that mankind was able to get more accurate reading on the speeds that certain fish swim at.
How Do Fish Live In A Frozen Pond?
Having previously lived on a farm that had a number of large ponds, and often being snowed in, thinking about the fish in the frozen water occasionally crossed my mind. Now, I know that ice, is lighter than water, and therefore it floats. Generally, what we call a frozen pond is a pond of which the surface is frozen.
Ice skaters of yesterday (primarily) skated upon such ponds. Individuals like my husband, who are prone to tempting fate, also like to go sliding and walking about on such ponds. The first thing both, hopefully, will do is to know how thick the ice is, for they know that there is liquid water underneath it.
So when I speak about fish living in a frozen pond, I mean fish living in liquid water that has a layer of frozen water above it.
The really serious part of this for the fish is not, as one might think, the coldness of the water they are in, but the question of how that water is to be supplied with enough air for the fish to live.
When a pond is not frozen, oxygen from the air above is passing into the surface of the water as fast as it is being used up by the fish and the thousands of other living creatures in the water.
When a pond is frozen, this process is very nearly stopped. There may be gaps in the ice here and there -- air holes, such as air-breathing creatures will make in the frozen north -- but perhaps there may be none of these.
A little oxygen may get through at the edge of the ice, but the best hope for the fish is that there is a supply of new water coming into the pond below the ice from somewhere else, and bringing enough oxygen dissolved in it to keep the fish alive.
If the supply of oxygen is kept up in none of these ways, then, when there is no more of it left, the fish will surely die, as must every living creature that can no longer get oxygen.
How Is It That Fish Don't Drown? (Usually)
That question was asked of me by my daughter when she was a little girl. The answer is that all animals and plants must get air to live, or, to be more accurate, they must have oxygen. Should this supply of oxygen fail, death must come, whether from drowning or from any other cause.
What really happens when a man is drowned is that, on account of his being so long under the water, his supply of oxygen, has run short. Water contains oxygen, just as air does, but human beings and animals that breath by lungs cannot make use of it.
Lungs are made so that they can extract the oxygen from the air, but not from water.
Fishes do their breathing with gills, instead of lungs, and gills can extract the oxygen from water, but not from air.
therefore, fishes cannot breathe on land, but are able to breathe perfectly well in water.
However, if anything should happen to prevent the fish from getting oxygen from the water, or if the water were deprived of its oxygen, the fish would drown.
Why Do Fish Often Die In A Tank Of Water?
We've had more fish die over the childhood years of my oldest granddaughter than any family I know. Why do her fish in a tank of water die? Lots of reasons, among them:
- Mostly, the general reason here is that some varieties of fish placed in a tank of water often use up all the oxygen that is in it quite quickly if not aerated properly.
- Changing the water often in order to supply them with fresh oxygen is one remedy.
- Green plants in the tanks are another helpful solution for keeping the oxygen levels correct is another. Having the right tank with the right air filter bubblier is another solution.
- Overfeeding them and not feeding them enough have been other lessons learned.
How Is It That Fish Are Not Salty When Caught In The Ocean?
We must remember that the fish, like ourselves, have the power of taking into its blood from the food it swallows just those substances that it needs.
When we study the whole animal world, we find that the proportion of salt in the bodies of many different creatures is much the same.
The cells that make muscle, or flesh, are not very different in their way of living, or in their needs, whether they are in a bird, a fish, a cow, or ourselves.
A fish that has lived in salt water does not taste saltier than one that has lived in fresh water. Fish that taste salty, simply have been prepared that way by methods of cooking or preserving.
If You'd Like To Know More!
- Fastest in the Sea
Sailfish are a very well-known species of fish (you've probably heard of them, and maybe even seen one mounted) because of their popularity among sport fisherman. They are world-renowned for the challenge they provide even the most experienced angler
- How Fast Can a Shark Swim?
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- How fast can fish swim | Bish on Fish in New Zealand Blog
A list of the fastest ocean fish