The piranha is a freshwater fish from South America. It thrives in schools in the streams and lakes of the rainforests of the Orinoco River and Amazon basin. All known species of piranha fish belong to two genera, namely Pygocentrus and Serrasalmus. Piranha schools are known for their vicious feeding frenzy, but this phenomenon occurs only when there is a shortage of food. According to stories, they consume their prey until only the bones are left, but this occurrence is quite rare. They hunt in groups, but they also maintain these large schools in order to defend themselves from natural predators such as birds, caimans, otters, turtles, water snakes, and human beings.
Diet of Piranha
Piranhas are omnivores, but they are better known as flesh-eaters or opportunistic carnivores. While individual piranha fish would eat only smaller fish, piranha schools can and will attack and devour small mammals and larger fish. Some of the animals that often fall prey to schools of piranha are crustaceans, birds, amphibians, and lizards. They also eat land animals that venture into their native habitat. They are most active and aggressive during the day. Smaller piranha fish hunt mostly at dawn, while larger piranha take their fill in the evening or late afternoon.
Aside from its almost mythical feeding behaviors, perhaps the notoriety of the piranha is closely tied to its most prominent anatomical feature-the razor-sharp teeth. The piranha has a large and strong lower jaw full of sharp teeth. The upper and lower jaws are lined with an even row of teeth. When one is broken it is immediately replaced with a new growth.
Reproduction of Piranha
Learning accurate piranha fish facts helps us understand better the fish known in Venezuela as the “caribe.” They lay their eggs in the lakes and rivers of the tropical rainforest. Their main breeding grounds are the lagoons. The female lay groups of eggs in nests dug in the sediment in the shape of a bowl. The male fish then fertilizes the eggs. When piranhas are spawning, the belly of the fish becomes reddish in color, while the rest of the body becomes lighter. Piranha breeding behavior in the wild is somewhat similar to that of birds. When it is nesting season, the adult piranhas patrol their spawning territory in order to defend the eggs.
Piranha fish and humans
South American fishermen catch piranha fish and eat them. They are also a staple food product in local wet markets. Aside from food, the piranha is useful to humans as a source of effective cutting tools. The upper and lower jaws of the fish with its sharp teeth are gathered and used in activities that require shearing and puncturing. When packed tightly, piranha teeth can also be used as a formidable weapon. For the tourist trade, some locals dry the whole specimen under the sun and sell them to tourists as souvenir items.
Swimmers in freshwater rivers and lakes where piranhas are known to live have reported being bitten or injured. Nevertheless, most of the bloody stories about mutilated body parts are exaggerated accounts. Locals would swim in waters that serve as natural habitat for piranha and usually come out unscathed
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