Parent-child relationships among fish vary widely, ranging from complete disinterest in freshly hatched eggs to a state of constant alertness and protection of the offspring. Most of the time, only one parent takes care of the eggs or small fry.
This is not the case for the discus fish, the most beautiful of the cichlids, a freshwater fish native to the Amazon basin and highly popular for its adaptability to aquariums.
The parents take turns standing guard, watching over and incubating the eggs. Once the eggs hatch, they take the newborn fry into their mouths and transfer them to a surface where each fry becomes attached, wriggling at the end of a short filament. The fry begin to swim freely four days after being born.
To feed the tiny fry, the parents secrete a mucus from their skin, which the eager fry quickly suck up. Although both parents can feed the offspring, they take turns and alternate resting periods. With a flick of their bodies, they transfer all the fry to their partner.
“One cannot defend what one does not love, and one cannot love what one does not know.”