Why fish love to swim against the current of the Fen River

It is a truth in his heart and for a man to be very good to himself.

The first thing to say is that the final destination of almost all rivers is the sea, and freshwater fish cannot survive when they enter the sea, so the ancestors of the fish found that as long as they go upstream, they can not die, so this instinct is engraved into the DNA and passed down from generation to generation, and it is instinct for fish to swim against the current now.

The fish swim back because they live in the water. Different water quality breeds fish with different habits And fish, like people, have the nature of life, and where they are born, they always have to return to them. (Maybe it's for peace of mind).

The fish of the freshwater river never said that they wanted to jump into the sea. But all life wants to find the best quality living environment.

It is always easy to swim against the current, and the water is relatively deep, the water pressure and air, for some fish are more difficult to survive, and the higher the water, the more air and light are more abundant, and the food is more, which will naturally be attractive.

Fish have a top-current swimming trait, which is convenient for fish orientation and feeding. When the current velocity is less than the critical velocity, the fish does not react to the current, when the current reaches a certain level, the activity of the fish increases, and it actively swims at the top of the current, and when the current speed is too large and exceeds the limit swimming speed, the fish also maintains the top flow state and is washed away by the current.

The respiratory organs of fish are the gills, and the gill filaments in the gills are covered with capillaries that absorb the oxygen dissolved in the water. When the fish swims upstream, the water flow is relatively fast, which increases the gap between the gill filaments and better absorbs oxygen. Coupled with the fact that the water is fast, it can also replenish the fish's oxygen needs in time, so the fish like to swim against the current!

It is convenient to eat plankton down the river. Swimming against the current in search of spawning grounds is the behavior of some species and is seasonal.

Small, planktonic creatures that eat down the river, and there are also fish species that go against the current in search of spawning grounds.

Lay eggs. Shallower waters and abundant plankton are required for spawning, and swimming upstream provides such an environment.

Timely replenish the oxygen needs of fish to mate and spawn upstream.

There are many reasons why fish swim against the current:

1. For example, some fish feed on planktonic organisms, and this kind of creature can only drift with the tide because it is very small, and the fish can swim against the water to hunt more easily.

2. In addition, the fish is to breathe, the fish needs to make the water in and out of the gills when breathing, which is why the fish are also swimming when they are sleeping, and the water flow in and out of the water is relatively faster against the water, and sometimes this is necessary.

3. Some species of fish have migratory characteristics. These fish are freshwater (rivers) and long in saltwater (oceans), and when they are born, they remember the smell of their birthplace and swim back there en masse when they need to mate and spawn. Since it is swimming from the sea to the river, it is against the current.

Go upstream to mate and lay eggs.

And it is good for predation.

Because its scales are uncomfortable when swimming downstream!

I don't understand, but some people don't talk nonsense??

Live fish swim upstream, and dead fish go with the flow. Well, I looked it up online. However, strictly speaking, there are fish that swim upstream, such as salmon, which is a salmon that goes up against the current to spawn every year, and there are many fish that go with the current.

When a fish swims upstream, it means that it has to go far away to spawn, such as salmon. This is the process of life, just like a person has to have children. For the sake of future generations, they have to go against the current.

I stand up to the brother above's answer, but my own opinion is that fish like people like to challenge black and black.

Not so the fish have a preference for retrograde. This may be their habit.