piranha
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What is a piranha?
Piranhas, also called caribe or piraya, are any of more than 60 species of razor-toothed carnivorous fish that reside in South American rivers and lakes. While they have a somewhat exaggerated reputation for ferocity, most piranha species are scavengers or feed on plant material.
Piranhas typically do not grow larger than 60 cm (2 feet) long and display colors ranging from silvery with orange undersides to almost completely black. They possess deep bodies, saw-edged bellies, large, blunt heads, and strong jaws equipped with sharp, triangular teeth that create a scissorlike bite.
These fish are most diverse in the Amazon River, where 20 different species are found. The red-bellied piranha is the most infamous, known for having the strongest jaws and sharpest teeth.
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Where do piranhas live in the wild?
Piranhas are a diverse group of fish, with over 60 species inhabiting South American rivers and lakes. Their distribution ranges from northern Argentina to Colombia, with the greatest variety found in the Amazon River, where 20 different species reside.
The red-bellied piranha is the most well-known species. Other notable species include the lobetoothed piranha, found in the Orinoco River basin and Amazon tributaries, and the San Francisco piranha, native to Brazil's San Francisco River.
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What do piranhas eat?
Piranhas, found in South American rivers and lakes, have a somewhat exaggerated reputation for ferocity. Though depicted as ravenous killers in movies, most piranha species are scavengers or feed on plant material.
The red-bellied piranha is the most infamous, with strong jaws and sharp teeth. They hunt in groups, especially during low water, and converge in feeding frenzies if a large animal is attacked, though this is rare. They typically target prey that is slightly smaller than themselves.
Most piranhas do not kill large animals, and attacks on humans are rare. Some species, like the wimple piranhas, eat morsels nipped from the fins and scales of other fish, which are able to heal completely.
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What do piranhas look like?
Piranhas are any of over 60 species of razor-toothed carnivorous fish residing in South American rivers and lakes. Most never grow larger than two feet long. Piranhasâ colors range from silver with orange undersides to almost completely black.
These common fishes have deep bodies, saw-edged bellies, and large, generally blunt heads with strong jaws. Their sharp, triangular teeth meet in a scissorlike bite. The most infamous is the red-bellied piranha (Pygocentrus nattereri), known for having the strongest jaws and sharpest teeth of all.
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How do piranhas hunt and defend themselves?
Piranhas are South American fish with a reputation for ferocity, though most are scavengers or herbivores. The red-bellied piranha is the most infamous, possessing strong jaws and sharp teeth.
Red-bellied piranhas hunt in groups of over 100, especially when water levels are low. They typically target prey that is slightly smaller or of equal size. A scout piranha signals the rest, likely using acoustics due to their excellent hearing. The group rushes in to bite the prey before retreating to allow others to feed. Though attracted to blood, most piranhas scavenge more than they actively hunt. Some species, like the wimple piranhas, feed on the fins and scales of other fish.
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What are some common myths or facts about piranha behavior?
Piranhas are known as razor-toothed carnivorous fish, but their ferocity is somewhat exaggerated. In movies, like Piranha (1978), they are depicted as indiscriminate killers, but most piranha species are scavengers or feed on plants.
The red-bellied piranha is the most infamous, with the strongest jaws and sharpest teeth. They hunt in groups of over 100, especially when water levels are low. While several groups can converge in a feeding frenzy if a large animal is attacked, this is rare. Piranha attacks on humans are rare because most species scavenge more than they kill, despite being attracted to blood. Some species, like the wimple piranhas, eat morsels nipped from the fins and scales of other fish.
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piranha, any of more than 60 species of razor-toothed carnivorous fish of South American rivers and lakes, with a somewhat exaggerated reputation for ferocity. In movies such as Piranha (1978), the piranha has been depicted as a ravenous indiscriminate killer. Most species, however, are scavengers or feed on plant material.
Most species of piranha never grow larger than 60 cm (2 feet) long. Colours vary from silvery with orange undersides to almost completely black. These common fishes have deep bodies, saw-edged bellies, and large, generally blunt heads with strong jaws bearing sharp, triangular teeth that meet in a scissorlike bite.
Piranhas range from northern Argentina to Colombia, but they are most diverse in the Amazon River, where 20 different species are found. The most infamous is the red-bellied piranha (Pygocentrus nattereri), with the strongest jaws and sharpest teeth of all. Especially during low water, this species, which can grow up to 50 cm (about 20 inches) in length, hunts in groups that can number more than 100. Several groups can converge in a feeding frenzy if a large animal is attacked, although this is rare. Red-bellied piranhas prefer prey that is only slightly larger than themselves or smaller. Generally, a group of red-bellied piranhas spreads out to look for prey. When located, the attacking scout signals the others. This is probably done acoustically, as piranhas have excellent hearing. Everyone in the group rushes in to take a bite and then swims away to make way for the others.
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The lobetoothed piranha (P. denticulata), which is found primarily in the basin of the Orinoco River and the tributaries of the lower Amazon, and the San Francisco piranha (P. piraya), a species native to the San Francisco River in Brazil, are also dangerous to humans. Most species of piranhas, however, never kill large animals, and piranha attacks on people are rare. (See also Sidebar: Vegetarian Piranhas.) Although piranhas are attracted to the smell of blood, most species scavenge more than they kill. Some 12 species called wimple piranhas (genus Catoprion) survive solely on morsels nipped from the fins and scales of other fishes, which then swim free to heal completely.
Ichthyologists often separate the carnivorous âtrue piranhasâ from the vegetarian members of Serrasalminae. Typically, true piranhas are limited to three species of genus Pygocentrus: P. piraya, P. nattereri, and P. cariba. Historically, however, other classifications have expanded the group to include four genera: Pristobrycon, Pygocentrus, Pygopristis, and Serrasalmus, based largely on the single row of sharp triangular teeth all members display. Still other classifications include additional genera, such as Catoprion, or exclude Pristobrycon because that group is not considered by all ichthyologists to be monophyleticâthat is, descended from a single common ancestor.