<P> Foraging methods vary throughout the different stages of a piranha's life . Smaller fish will search for food during the day, while larger fish will forage at dawn, in the late afternoon, and in the early evening . Throughout the day, the fish lurk in dark areas and ambush their prey . The piranha may also catch prey by hunting and chasing, where it will lie hidden in the vegetation until its prey swims by . The piranha will then capture its prey . When scavenging, the piranha will eat a wide variety of food, ranging from pieces of debris, insects, snails, fish fins and scales, and plants . </P> <P> The breeding habits of piranhas in nature are mostly unknown, with most spawning research being done in aquaria . Piranhas are usually able to breed by the time they are one year old . Female piranhas will lay several thousand eggs near water plants, onto which the eggs stick . The males then fertilize the eggs . After just two to three days the eggs will hatch, and the juvenile piranhas will hide in the plants until they are large enough to defend themselves, at which point hiding from predators becomes lurking for prey . </P> <P> Research on red - bellied piranha breeding behavior in nature has revealed certain behavioral patterns around nesting sites . Adult piranhas will swim side - by - side in small circles, sometimes with two individuals swimming in opposite directions while keeping their ventral surfaces close to one another . Although this may appear to be a courtship display, a closer look reveals that the adults are actually defending nesting sites . The nests are about 4 to 5 cm deep, and are dug amongst water grasses, with the eggs attached to the grasses and plant stems . </P> <P> This formation of mating pairs, nuptial swimming displays, and guarding of the nests shows that red - bellied piranhas exhibit parental care for the nest and the young . When left unattended, other fish, such as characids, may prey upon the eggs . Despite the defensive practice of circling the nests, red - bellied piranhas are often passive towards other fish that approach the nest . It is possible that the mere presence of the piranha, a natural predator, provides enough of a threat to prevent potential predators from approaching the nest . </P>

How long can red belly piranhas go without food