In about 25% of all fish species, at least one parent takes care of the eggs and/or the young. The ways in which they provide care vary greatly: some species clean the eggs and fan fresh water over them, while others even feed their larvae. These efforts help the offspring survive during a particularly vulnerable stage of life. In European catfish, the male guards the eggs after spawning, protecting them from predators and fanning fresh water over them every three to five minutes. Female Nile tilapia carry the eggs and larvae in their mouths for twelve days and later allow the young to swim back into their mouths when danger approaches—during this entire period, they cannot eat.
Picture: Mozambique Tilapia (Oreochromis mossambicus) raising young in its mouth.
Source: Fischwissen.ch
