Every time we read the sentence "The Yellow River comes from the sky and flows to the sea, we can't help but feel the majesty and magnificent scenery of this river, but at the same time a very interesting question will also appear in our minds, since the Yellow River's water is rapid and fierce, how do the fish living here survive?
If you can not resist the powerful rapids washed into the sea, it is likely to go directly into the ghost, because the vast majority of fish living in the river are not able to survive in the sea, we will take a look today, the Yellow River where the fish have gone.
Freshwater and saltwater fish
First of all, fish are divided into freshwater fish and saltwater fish according to the different living environments, freshwater fish generally live in rivers or lakes, and seawater bathing is the fish in the sea, because of the difference in water quality, the body structure and adaptability of these two types of fish is different.
For example, saltwater fish need is higher salinity, pressure is also greater water, if suddenly put into fresh water inside, the normal functioning of the body will be affected, because the pressure of the external environment is not enough, there may also be the phenomenon of body expansion or even rupture.
Conversely, freshwater fish, if released into the sea, will soon die in a very short time due to the cellular water loss that occurs with high salinity, coupled with excessive external stress.
Then you may say, the water cycle can be completed is because the various water systems are linked together, the fish are also likely to migrate and other processes into other waters by mistake, so will not there be fish die every day as a result?
In fact, the body of fish have a very sensitive perception system, when the surrounding water environment suddenly appeared some small changes, they can quickly detect and timely response, if the salinity or pressure and the original environment there are significant differences, the fish will immediately change the trajectory of activities, back to their own adaptation to the waters.
It is true that fish living in the Yellow River are washed into the estuary because of the flood rapids, but this does not mean that they do not have the possibility of surviving.
First of all, the mouth of the sea is actually still at the confluence of the river and the sea, even if there is a certain amount of seawater component, but the river also plays a great role in dilution, so the salinity is not as high as we thought, a significant portion of the fish can continue to live in this area, but the fate of the next will have to rely on their own to fight.
For the part of the survival desire is particularly strong, they will aim at the time, after the current is a little smaller re-enter the river, and then all the way back upstream, back to their original survival environment.
Of course, generally speaking can do this are relatively large fish, such as the Yellow River sturgeon, although they are relatively large, or will be swept into the sea by the rapids, but can again swim back to the Yellow River by virtue of their strong migratory ability, can be said to be a model of rapids.
Then the question arises, if the size is not big enough, and the strength is not strong enough, is it a certain death?
In fact, the fish are not as stupid as we think, they can also be summarized from the survival of the environment experience, after millions of years of observation and accumulation, for when the river will enter the flood season, when will threaten their survival, they have a very clear perception, and in fact, most of the Yellow River fish live in the downstream area, because the terrain is more gentle, the water flow environment is also more stable.
But even so, spawning here is very dangerous, after all, the eggs do not know how to avoid the risk of being washed away by a slightly stronger current.
So during the spawning period, these fish will start migrating, swimming against the pressure of the rapids all the way back to their birthplace and then spawning there so that they can avoid the situation where their offspring cannot be born successfully, and when these eggs hatch successfully into small fish, they will also go downstream along the river to the resource-rich lower reaches.
Of course, this whole process will take a long time, before they successfully arrive, they are usually almost grown up, and the next is to wait for the right time to return to their birthplace to start the new generation of reproduction, as the parents once did, and so on and so forth, so that the Yellow River can retain the rich fish resources in spite of the rapid and violent current.
And from the results of the data survey, although the Yellow River is rapid, but only a very small part of the real washed into the estuary, the vast majority of them are able to stay in the downstream river.
But as the saying goes, the world is full of surprises, so there is no fish that can live in fresh water and also adapt to the seawater environment?
The answer is that there are indeed, such as the Yellow River mullet, their approach is to adjust their body's adaptation mechanisms in time to cope with changes in salinity and pressure and other factors when they are in different waters.
For example, after entering seawater from fresh water, this fish will take the initiative to drain the water out of the body, until its body fluid concentration and the concentration of seawater to reach an equilibrium, so that the pressure does not damage their organs in the body.
This fish, which looks somewhat similar to the striped bass, is precisely because of this special ability to ensure that they will not be affected after being washed into the sea, and can be said to come and go as they please.
In addition, it is also migratory, so in the Yellow River is also considered a fairly strong survival ability of a fish.
In addition, fish do not want to be swept away by the rapids, in fact, there is a way to enter the Yellow River tributaries or lakes, even in the flood season, at most, the water level rises, basically there will not be a threat to the survival of the problem.
In general, although the Yellow River does have a flushing of fish into the sea, it does not exist in large numbers, and the fish that have lived here for a long time have figured out a way to cope with it without affecting the biodiversity of the basin overall.