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Fish reproduction
Fish reproduce in a number of different ways. In most fish species, the female lays hundreds of small eggs, which the male fertilises by releasing his sperm in the water nearby.
Some species of fish defend their young by building nests to lay their eggs in, whilst other species keep their offspring in their mouths until they are old enough to take care of themselves.
The water provides the developing eggs with dissolved oxygen and nutrients, although the chances of each fertilized egg surviving to adulthood are very low as they can fall prey to predators or be destroyed by currents and tides.
In most species of fish, larvae hatch from the eggs and develop their skeleton, fins and organs as they mature.
Banggai Cardinal Fish
Find them in B.U.G.S!
Banggai cardinal fish swap roles when they reproduce. The female courts the male, twitching and shimmying around him, before laying her eggs. After fertilizing her eggs, the male keeps them in his mouth for up to twenty-four days whilst the female guards him. A few days after they hatch, the male spits the young Banggai cardinals out near a long-spined sea urchin to give them some protection from predators.
Pitch Lake Guppy
Find them in B.U.G.S!
A livebearing and very fertile fish, the female guppy can store sperm in her body and produce a number of litters after mating only once. Fertilization is internal and young guppies can be seen developing through their mother’s skin. Females give birth between twenty and forty offspring, able to swim, hide from predators and find food - which is lucky because the parents sometimes eat their young!
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