Fishes

Most female fishes lay their eggs in open waters and the males fertilize these. This means that the eggs develop outside the parent’s body. Parent fishes do not protect their soft, jellylike eggs, thus exposing the eggs to all kinds of dangers in their environment. This decreases the eggs’ chances of survival or of even hatching.

Fishes lay many eggs to ensure that enough young will survive despite the dangers in their surroundings. When the fish eggs hatch, the young called fry look very much like the adult fish. They also start to feed on their own. Depending on their species, they go through several developmental stages before they are fully grown.

Even with the great numbers of fry that are hatched, many do not survive to adulthood because of changes in the temperature and oxygen levels of the water and also because of predators. Despite this, billions of fish still survive to the final stage of adulthood in different bodies of water everywhere. When the adult female is ready to reproduce, she releases millions of eggs into the water and the cycle is repeated.