The fish world is very diverse. Most species reproduce with eggs, but viviparous fish also exist. The methods of throwing eggs, the conditions in which this process takes place, also differ. Even viviparous fish, depending on the species, produce fry in different ways, the degree of readiness of the young for independent existence depends on this.
Instructions
Step 1
Many fish reproduce by spawning, but different species do this differently. For example, such a species as atherina-grunion swim as close to the shore as possible and at high tide find themselves on bare sand, it is in this wet sand that they lay their eggs, after which it is fertilized by males. In atherina-grunion, the process of laying and fertilizing eggs occurs very quickly, because they must be in time before the next wave overtakes them. The fry hatch from the eggs pretty soon, and with the onset of the tide, the babies go to the ocean.
Step 2
Salmon caviar is appreciated as a delicious and healthy delicacy. Interestingly, salmon fish migrate from salty waters to freshwater bodies for spawning. These fish work together - in pairs. The male and the female pre-dig a kind of nest at the bottom of a freshwater reservoir, while at the same time they protect the vending territory from competing fish. A very important point for salmonids is that the germ cells of both parents appear in the water at the same time, otherwise fertilization will not occur. Many salmon species are capable of reproduction only once in a lifetime, to a greater extent from the fact that they simply die after spawning. For example, this is the case with the Pacific salmon.
Step 3
In nature, of course, there are viviparous species of fish. They do not spawn, but give birth to already fully formed offspring - fry, which can immediately live and develop independently. One of the strange features of viviparous fish is that after throwing fry, a mother can easily eat her own cubs, she simply cannot distinguish them from other food.
Step 4
There are also such species of viviparous fish, in which fry feed with the help of the mother. They are attached directly to her body. In others, fry hatch from eggs, but this happens inside the mother fish, just before birth. Some shark species are viviparous fish. Aquarium enthusiasts are well aware of such viviparous fish as swordtails and guppies. These are very unpretentious creatures largely due to the fact that they are born in the form of fry already adapted to existence.
