The piranha, known by the nickname “water wolf,” is a species of carnivorous freshwater fish primarily found in the rivers and lakes of the Amazon Basin.
With its sharp teeth and aggressive nature, the piranha is a source of fear for both other animals and humans. However, despite its ferocity and danger, the piranha has not proliferated throughout the Amazon. The reasons for this phenomenon can be explained through various aspects, including habitat, the species’ behavior, and competition from other rival species within the same ecosystem.
The Amazon River, often called the “lungs of the Earth,” holds countless wonders and mysteries. Among its fierce predators is the piranha, a name that cannot be overlooked. With its razor-sharp teeth and aggressive nature, the piranha is portrayed as an “underwater killer,” instilling fear in its prey.
1. Piranha: Abilities and Characteristics
Piranha, also known as red-bellied piranha, is the most aggressive piranha species towards humans. They possess razor-sharp teeth arranged in two dense rows, with up to 30 teeth in each row. The biting force of a piranha can reach up to 350 psi, three times that of a human, allowing them to easily tear apart their prey.
This fish species also has an extremely keen sense of smell, enabling them to detect blood from a distance, even from a small drop diluted in 1,000 liters of water. Upon sensing blood, piranhas will gather in schools and attack their prey aggressively.
In the Amazon River Basin, local residents must learn to act cautiously when facing piranhas. For instance, if cattle herders encounter rivers or lakes inhabited by piranhas, they will drive a sick cow into the water to lure the piranhas away before safely crossing the river.
When schooling, piranhas become more aggressive and courageous.
Piranhas are highly social animals, often living in schools of up to hundreds of individuals. When in schools, piranhas become fiercer and bolder, effectively coordinating their attacks on prey, overwhelming them with numbers.
2. Why Can’t Piranhas Dominate the Amazon River?
Despite their many aggressive traits, piranhas cannot dominate the Amazon Basin. This is mainly due to their own limitations as well as the presence of strong competitors within the ecosystem.
Piranha Limitations
Even though piranhas have sharp teeth and a powerful bite, they have their own weaknesses. One of the shortcomings of piranhas is that they primarily act as scavengers. In addition to hunting some fish, crabs, insects, and occasionally birds, frogs, and lizards, piranhas mainly prey on weak, sick, or injured creatures.
Piranhas are not voracious predators. If they are full, they are unlikely to pay attention to prey and will retreat. Furthermore, despite their fierce appearance, they are actually cowards, especially when alone. They only become truly dangerous when they appear in groups.
Piranhas are scavengers, primarily preying on fish, crabs, insects, birds, and frogs.
However, in rare cases, piranhas can attack humans, particularly when a person is injured and bleeding.
Competition in the Ecosystem
The Amazon Basin is not a peaceful place, and piranhas face many formidable competitors. One of their rivals is the electric eel. Electric eels can discharge voltages ranging from 300 to 650 volts, and in some cases, can exceed 800 volts. Continuous strikes from an electric eel can kill a cow, and they have been known to kill piranhas as well.
Other fish species like the spiny catfish, which are very adept at using their sharp spines, are also serious competitors for piranhas. Additionally, there are crocodiles and many other animals that can attack and prey on piranhas.
Despite their ferocity, the number of cases of piranhas harming humans is very low.
The Amazon is home to countless other predatory species, creating an ecological balance. Piranhas are just one part of the food chain and cannot completely dominate the ecosystem. Piranhas face many larger and stronger enemies such as crocodiles, otters, and electric eels. These predators can easily eliminate piranhas, limiting their numbers.
Although piranhas are dangerous and aggressive, they have not been able to spread throughout the Amazon Basin. The presence of many strong competitors and their own behavioral and dietary limitations have prevented piranhas from dominating this ecosystem.
Piranhas rank only fourth among the recognized killers of the Amazon. At the top of this list is the spiny catfish, a freshwater species highly skilled at using its sharp spines.
While piranhas are very dangerous, the number of cases of piranhas harming humans is very low. As long as you are uninjured and swimming in areas with piranhas, they typically will not attack you. Additionally, piranhas can only survive in tropical regions with temperatures above 20 degrees Celsius year-round, which limits their habitat globally.
