Predatory piranhas. Two years ago, the message about piranhas in the Rostov region sounded like this (News)

Piranhas are river hyenas, very dangerous for all mammals and humans, predatory fish. Hearing the word “piranha”, a person will immediately imagine film footage of a huge toothy fish chasing a man. There is some truth in this idea.

Share - because not all piranhas are predators, and they are not such huge fish. Its average size is 35–50 cm, but there are specimens up to 80 cm.

What types of piranhas are there?

There are piranhas that only eat aquatic plants. These include the species Colossoma bidens. The remaining representatives are predators. Lives in fresh water bodies South Africa about fifty species, the exact number is unknown.

They choose different habitats - some species live in quiet, slow waters, while others prefer swift and rapid currents.

Some of them are bred at home. A flock of quiet, small fish will decorate any aquarium. They are fed squid, capelin and meat.

In nature, there are several species of predators, the most dangerous is the species Pygocentrus nattereri.

Features of appearance and behavior

Piranhas vary in size, head shape, and shades of skin color. Basically, the coloring of adult piranhas is silvery-olive on the back and sides. The abdomen has a purple or red tint. The very edge of the tail is bordered by a bright black line.

But its most distinctive feature is its teeth. When its mouth is open, its triangular teeth measuring 5 mm in size look terrifying. Moreover, they are designed in such a way that when a piranha clenches its jaws, the upper teeth fit tightly between the lower ones, forming something like a solid sharp razor.

The jaws are driven by very strong muscles, thanks to which sometimes a bite with only the front teeth is sufficient.

With them, she not only tears out pieces from the victim, but can also bite through bones and veins. There are known cases when piranhas easily bit off a human finger or a thick stick.

Piranhas are the only “talking” fish!

Most fish in nature do not make any sounds. Piranhas are an exception to this rule. Surprisingly, they can croak when they get close to each other. When fighting, the sound they make is similar to drumming. When they are taken out of the water, you can hear sounds reminiscent of angry barking.

All species of these fish have excellent hearing and sense of smell. They can smell and hear prey at a distance of 7 km. Moreover, literally a drop of blood from the slightest wound on its body is enough for the piranha to instantly rush to feast.

Schools of fish immediately rush to the place where the prey is located. They are not afraid of either large animals or fish, which can be 10 times larger in size. If one of the piranhas itself receives a wound, then it is likely that its relatives will attack it too. Even a crocodile can give up in front of a pack of these ferocious predators and tries to quickly swim away, turning over with its belly up for safety.

Many stories are associated with the gluttony of piranhas. There is a known case when a flock gnawed to the bones a pig that had fallen into the water. Fishermen are often their victims. Piranha meat is edible and resembles perch. It is especially tasty when fried. They catch it with a fishing rod, and if the fisherman is careless when removing the fish from the hook, then it can snatch off his finger. Not in vain from the tongue different nations The name “piranha” is translated as “toothed devil”, “evil fish”, “pirate”.

But more often than not, all these stories are exaggerated. Piranhas become aggressive only when water bodies dry up. The fish have nothing to eat and have to eat everything they can find. During the rainy season, when the rivers are full of water, people swim and ride boats calmly next to swimming piranhas.

The common piranha (Pygocentrus nattereri) is a predatory ray-finned fish well known to most aquarists, belonging to a fairly large family of piranhas (Serrasalmidae). Aggressive exotic fish can be kept at home, but for successful cultivation you need to take into account the biological characteristics of the piranha, as well as provide it with the most comfortable living conditions.

Description and characteristics

For those involved in aquarium fish farming, the common piranha is better known as the red-bellied, red, or Natterer's piranha. The very first predatory exotics appeared among domestic aquarium hobbyists more than fifty years ago, and were brought to the territory of our country in the last century from the natural reservoirs of the Amazon and Orinoco.

The average length of the fish, as a rule, varies between 10-20 cm, but larger individuals are also found. All varieties differ in color, which in most cases is olive green or black with blue. The ventral part and sides most often have a dark or silver-gray color.

A characteristic species feature of piranha is big mouth and protruding, flat, wedge-shaped teeth with a sharp apical part, which allows the predator to bite even into the very hard skin of its prey. On both jaws, the teeth have absolutely the same structure, but the upper row is smaller, and when the mouth is closed, it is located in the spaces between the lower teeth. The jaws function under the influence of powerful muscles. Distinctive feature of the lower jaw is its shift forward and a fairly pronounced bend of the teeth back.

Natural distribution area

Piranha is a schooling fish. IN natural conditions this exotic predator gathers in very large flocks that inhabit natural bodies of water located on the territory of the South American continent. Natural environment habitats are the Amazon, Paraguay, Parana and Essequibo, but the largest populations are recorded in countries such as Colombia, Venezuela, Guyana, Paraguay, Brazil and Central Argentina.

River predatory fish prefers to hunt prey in shallow or muddy water, and therefore is somewhat less common in the sea, where this predatory exotic fish is deprived of the opportunity to spawn. Spawning period in natural habitat habitat occurs between May and August. Gluttony forces the piranha to settle in reservoirs that abound in fish.

This is interesting! Piranha is a kind of river orderly, so, as a rule, only weakened or very sick aquatic inhabitants become its prey.

Features of keeping in captivity

Home breeding of piranha is extremely rarely accompanied by difficulties. In addition to the common piranha, domestic aquarists quite actively breed:

• piranha is slender;
• dwarf piranha;
• flag piranha;
• metinnis vulgaris and lunar;
• red or red-bellied pacu;
• mile redfin.

Aquarium piranhas are amazing, very timid and cautious creatures, so with sudden movements during transportation or catching, the fish quickly falls to the bottom. The exotic predator regenerates quite actively, and the skin and damaged fins are able to recover well.

Important! A school stocked in an aquarium must consist of fish of the same age and size. It is recommended to stock one species in one aquarium, which will prevent conflicts and stress.

Neighbors for predatory fish need to be selected correctly, giving preference to neons, minors, and swordtails, as well as armored catfish.

Arrangement of the aquarium

One school of piranhas, consisting of five to eight fish, should be kept in an aquarium, the volume of which can vary between 170-200 liters. Young individuals can be placed in a smaller aquarium, but for adult individuals, on the contrary, an aquarium with a water volume of 300-500 liters is desirable. When decorating, various design elements can be used, including stones of different sizes, natural driftwood, as well as live vegetation or artificial plants.

To fill the aquarium, water that has a slightly acidic or neutral reaction is used. Optimal pH values ​​should be 5.5-7. Comfortable temperature regime can vary between 24-26˚С. Well-oxygenated water must be kept constantly clean, for which a tenth of the liquid from the total volume of the aquarium is replaced daily. It is necessary to ensure high-quality aeration and filtration of water.

Behavioral features suggest the use of shelters and aquarium plants when arranging a significant part of the aquarium space, the total number of which should be about two-thirds of the total volume.

This is interesting! Teeth are used by aquarium piranhas, as a rule, for the purpose of self-defense, so aquatic vegetation is rarely damaged by them.

Piranha diet

In natural reservoirs, the diet of piranhas is very diverse, and in addition to other fish, the predatory exotic is able to feed on mollusks, various invertebrates, some amphibians, as well as fruits and seeds floating on the surface.

When kept in home aquariums, it is recommended to provide good nutrition, using for this purpose small fish, shrimp, squid meat, and earthworms. Among other things, you should definitely supplement your diet with chopped raw potatoes and zucchini, chopped white cabbage, chopped lettuce and spinach. A small open area is specially allocated for daily feeding.

To prevent the risk of obesity and disorders digestive system, you cannot feed piranha with chopped mammalian meat. Such food, if not completely eaten, quickly rots in aquarium water, and provokes habitat pollution that is harmful to fish. Good result and saving time comes from the use of specially developed dry food that has a balanced composition, enriched with all the necessary vitamin and mineral complexes.

Feeding rules

Important! Feed the aquarium piranha once a day.

The process takes a couple of minutes, after which the remaining food must be removed from the water. Through proper feeding, it is possible to adjust the tolerant attitude of individuals towards each other, as a result of which a strict hierarchy in the form of matriarchy is built within the flock. , which makes it easy to remove all food debris not eaten by fish and helps reduce the risk of water pollution. Fish do not eat food that has fallen to the bottom, so it quickly becomes a source of proliferation of pathogenic microflora.

During the first couple of months of life, daphnia, tubifex and bloodworms are used as food. Starting from three months, you can transfer fish to an adult diet, including meat. It is important to remember that a significant amount of meat in the diet increases the risk of infertility, so the volume of such protein foods should not exceed a quarter of the total diet. It is recommended that adult fish have a kind of fasting day four times a month, which reduces the likelihood of obesity in the internal organs.

Important! Pieces for feeding should not be large. In this case, it is possible to reduce feed losses.

The feeding process is a kind of indicator of the health of the piranha. If aquarium predators do not rush to food, then it can be assumed that the conditions are not correct enough.

Reproduction at home

The volume of which for a pair of fish should be approximately 300 liters of water. Stimulation of reproduction can be achieved by raising the temperature to 28°C, with a daily replacement of 25% of the water volume, increased nutrition and active aeration. You need to add a layer of small pebbles to the bottom of the spawning tank. The standard thickness of such a layer should not be less than 50 mm.

When creating the most favorable, comfortable conditions, the female piranha lays approximately 2-3 thousand eggs, placing them in a nest previously dug by the male. The male piranha also takes care of the emerging offspring. Larvae from the eggs appear in a couple of days, and already on the sixth day they transform into fry, for feeding which it is advisable to use cyclops, brine shrimp and chopped tubifex.

Precautionary measures

In aquariums with well-fed domestic piranhas, you can work with your hands, but it is very important that there are no wounds or bleeding lesions on the skin.

During the ongoing activities, it is strictly forbidden to drive a school of piranha into a corner or too narrow a place, since such a situation often provokes aggression in the fish. Most dangerous piranhas become during the spawning period, so work in an aquarium or spawning tank must be done extremely carefully, using special soft wire nets.

When choosing a variety, you need to consider some species features, as well as the opportunity to provide high-quality care for aquatic exotics. Mileus redfin or Mileus-luna is one of the most beautiful representatives of the category “herbivorous piranhas”. This species is unpretentious in care and growing conditions, so it is excellent for inexperienced aquarists.

Fast-growing red pacu can also do just fine plant foods, but during spawning this piranha needs exclusively live food. The view is not very suitable for those who are just starting to master aquarium breeding fish Metinnis vulgaris or mirror fish is rightfully considered the friendliest and slightly timid aquarium piranha.

They can easily tolerate some errors in care, and when properly maintained, they almost never show aggression. If you have a lot of experience, you can consider purchasing a slender piranha.

When purchasing exotics, you need to pay attention to the conditions at the point of sale.. The fish must be in clean water, in compliance with the feeding regime, therefore it is recommended to purchase live goods only by pick-up. It is most often not possible to correctly assess the health of a pet during delivery by courier.

Important! Healthy fish differ in behavior and appearance. Sick piranhas are passive or have poor coordination of movements. They have almost no appetite. The body of a healthy fish should not have lumps, ulcers or bulges unusual for the species, as well as a sticky or cloudy coating.

After acquisition, even fish that do not show signs of disease must be placed in a quarantine aquarium. After about a week, healthy individuals are placed in a permanent rearing aquarium.

You need to buy predatory exotics from trusted aquarists or specialists in breeding aquarium fish stores The cost of one individual depends on the type and age, but most often varies from one and a half to three thousand rubles. The cost of the rarest specimens sometimes reaches several thousand rubles for one young individual.

The common piranha has many different names - red-bellied, red or Natterera. If you apply one of these names to a domestic piranha, you won’t go wrong. The first predators appeared in the aquariums of exotic lovers more than 65 years ago. They were brought to our country in the middle of the last century from the waters of the Amazon and Orinoco.

It is worth noting that the most beautiful appearance in aquarium piranha it becomes at the moment of full puberty. The photo clearly shows the play of colors from the steel back, to the silver body and red belly, throat and anal fin. The red-bellied reaches about 30 centimeters in length wildlife and 25 in an aquarium. IN natural environment they live in flocks. The minimum number of individuals in one group is 20 tails. They unite to facilitate the search for food. Piranhas brutal predators, so they choose a victim and attack it in a flock. This species is considered the most ferocious of the inhabitants of the planet's waters.

Despite the fact that piranhas are not difficult to care for and are quite hardy, they are best kept by an experienced aquarist. Don't underestimate her sharp fangs and deadly grip. Inexperienced breeders can get into trouble with her through ignorance and carelessness. Under no circumstances should you place an aquarium with predators low if you have small children.

Piranhas are not suitable for multi-fish aquariums. They prefer the company of “their own”, but tragic cases cannot be ruled out there either. If you look closely at the habits, you can find the leader. He is always the first to eat, takes best places, shows who is the boss home aquarium, and, most often, the largest in size. It is not uncommon for fights to occur during clarifications. Aggression and cannibalism are possible. The only option with whom you can try to settle a piranha - a black pacu, provided that the latter has not reached puberty and is considered a teenager.

One piranha will live in an aquarium, but it is better to have several individuals at once. For large fish It is necessary to choose the correct displacement of the aquarium. Each individual requires approximately 150 liters of water; this same parameter should be taken into account if you decide to place several fish in an artificial reservoir. Piranhas are very voracious and, as a result, produce a lot of waste, so be careful about the choice of filter and its power. Active killers live in aquariums for at least 10 years, this should be taken into account before organizing an aquarium.

Water requirements:

• 150 liters per individual;
• A large number of shelters;
• The purest water and daily replacement of parts;
• Powerful filter with active filter element.

Carefully monitor the behavior of your pets and regularly do tests to determine the ammonia content of the water.

Nutrition

In their natural environment, these fish eat whatever they can catch, so the diet of piranhas is incredibly varied. It may include other fish, shellfish, various invertebrates, fruits and seeds from the surface, and amphibians. Officially confirmed facts are that a flock of more than a hundred individuals can attack large vertebrates, for example, capybaras. Most often, corpses and insects end up in their teeth. They become aggressive in times of hunger, drought, or constant attacks. The predator chooses sick and weak animals to attack.

Piranhas living in an aquarium happily eat foods such as:

• Fish.
• Shrimp.
• Squid.
• Earthworms.
• Heart.
• Crawls.
• Mice.

Beginning aquarists sometimes start feeding their fish with mammalian meat, but this should not be done, since the abundance of such food will inevitably lead to obesity and indigestion. In addition, undigested meat will come out and rot, severely polluting the aqua.

Reproduction

To distinguish a male from a female you will have to try. The only way is observation. The behavior of piranhas in a regular aquarium becomes characteristic before spawning begins. The males become much brighter, as can be seen in the photo, and the female’s body is rounded due to the accumulation of eggs in the abdomen.

To create a spawning tank, choose a quiet place. Despite all their aggressiveness, these fish are quite shy. You only need to contain compatible fish who have been “familiar” for a long time and have gotten used to each other.

Requirements for the spawner:

• Pure water;
• Hardness from 6.5 to 7.5;
• Temperature is about 27-29 degrees;
• Sufficient volume.

At the beginning of spawning, the pair will find a place convenient for laying eggs. After that, they aggressively guard the place they like. Now you will notice how the color darkens and a small nest appears at the bottom. After fertilization occurs, the male will fiercely defend the clutch from others.

The eggs have a rich Orange color. She will hatch on the third knock. After this, the larva will lie for another couple of days, and the fry will appear. Now you need to carefully catch the tadpole. Do this with a cage with a long handle, because the male guarding the clutch can attack any approaching object.

Are piranhas dangerous for humans? June 24th, 2018

From films and fiction books, we know that if you put your hand in the water where piranhas live, they will gnaw it off in a minute. Well, okay, maybe this is not accurate, but if there is some kind of wound on the body and blood gets into the water, then the piranhas can smell it a kilometer away and will definitely attack a person with the whole flock and certainly only a skeleton will be left of him.

Is this really true?

First you need to understand whether the piranha is really an extremely aggressive creature that attacks everything that moves in the water. This may sound unexpected, but piranha is a very cautious fish and does not pose any danger to humans. Exists a large number of evidence of a person swimming in piranha-infested water without any harm to his health.

This was fully demonstrated by Herbert Axeldorf, a famous biologist specializing in the study of tropical fish. To prove the safety of piranhas for humans, Herbert filled a small pool with piranhas and dived into it, leaving only his swimming trunks on. After swimming for some time among predatory fish and without receiving any harm to his health, Herbert took the fresh blood-soaked meat in his hand and continued to swim with it. But several dozen piranhas in the pool still did not approach the person, although quite recently they happily ate the same meat when there was no one in the pool.

Piranhas, considered fearsome predators with an insatiable thirst for fresh flesh, are actually quite timid fish and CARNARDERS, not daring to approach large creatures.

It is known that piranhas prefer to stay in large schools, and if one piranha is seen in the water, there are always others nearby. But piranhas do this not because it is easier for a school of predatory fish to overwhelm and kill a person who enters the water, but because piranhas themselves are a link in the food chain for other more large species fish Being in a flock of dozens of individuals, the chance that you will be eaten is quite low.

Moreover, experiments with piranhas have shown that when alone, these fish do not feel as calm as if they were surrounded by other fish.

But despite their peaceful behavior towards humans, piranhas are real killing machines for other fish species that are below them in the food chain. Their powerful jaws designed to bite and tear, and their dense, muscular bodies are capable of incredibly fast movements and jerks underwater. The piranha's jaw muscle contraction force relative to body size is believed to be the highest of any other vertebrate in the world. For example, the common piranha can easily bite off the finger of an adult.

But in history there has not been a single reliable case of a fatal attack by piranhas on a person. But this does not mean at all that these fish never bite a person or an animal that enters the water. And this behavior is almost always caused not by the aggressive behavior of the fish, but by self-defense or abnormal weather conditions, because of which the behavior of piranhas begins to differ sharply from usual. Abnormal weather conditions mean a period of drought, when the rivers in which piranhas live dry up, and many fish remain in depressions filled with water, but cut off from the main channel, deprived of food. Starving predators gradually begin to eat themselves and may well rush at any creature that comes close to the water. Sometimes the tendency of piranhas to behave aggressively is recorded during the spawning period, when they rush at a person or animal in self-defense, but such cases are extremely rare. And of course there is no talk of a collective attack by piranhas on humans.

Surprisingly, piranhas, being, according to many, one of the most the most dangerous predators, at the same time unusually timid! It is advisable to keep the aquarium in which piranhas live away from sources of noise and shadows, otherwise your pets will constantly be on the verge of fainting! It is a well-known fact among aquarists that a click on the glass or a sudden movement near the aquarium is enough for piranhas to faint. They also often faint during transportation from the place of purchase to their future home.

But all of the above does not mean that piranhas will refuse to eat human meat. Unfortunately, sometimes tragic incidents occur on the water - people or animals drown. An already lifeless body floating in the water attracts many fish, including piranhas, which leave specific bites on it. People who see this think that the cause of death was an attack by piranhas - this is how most myths about attacks by flocks of piranhas on people or animals are born.

And here's Paku for you - common name several species of omnivorous South American freshwater piranhas. The pacu and the common piranha (Pygocentrus) have the same number of teeth, although differences in their alignment are noted; The piranha has pointed, razor-shaped teeth with a pronounced mesial bite (the lower jaw protrudes forward), while the pacu has square, straight teeth with a slight mesial or even distal bite (the upper front teeth are pushed forward in relation to the lower ones). As adults, wild pacu weigh more than 30 kg and are much larger than piranhas.

here's more about them -

If you conducted a survey about which fish is the most dangerous on Earth, piranha would definitely be among the top three. Despite the rather small size of the fish itself, a school of piranhas in a matter of minutes will leave only a skeleton of a person who has fallen into the water. At least, this is what happens in numerous horror films and horror books. But is this really so?

The compressive force of the jaw muscles relative to body size is the highest in piranhas compared to any other vertebrate in the world.

First you need to understand whether the piranha is really an extremely aggressive creature that attacks everything that moves in the water. This may sound unexpected, but piranha is a very cautious fish and does not pose any danger to humans. There is a large amount of evidence of people swimming in piranha-infested waters without any harm to their health. This was fully demonstrated by Herbert Axeldorf, a famous biologist specializing in the study of tropical fish. To prove the safety of piranhas for humans, Herbert filled a small pool with piranhas and dived into it, leaving only his swimming trunks on. After swimming for some time among the predatory fish and without receiving any harm to his health, Herbert took fresh blood-soaked meat in his hand and continued to swim with it. But several dozen piranhas in the pool still did not approach the person, although quite recently they happily ate the same meat when there was no one in the pool.

Piranhas, considered fearsome predators with an insatiable thirst for fresh flesh, are actually rather timid fish that do not dare to approach large creatures.

It is known that piranhas prefer to stay in large schools, and if one piranha is seen in the water, there are always others nearby. But piranhas do this not because it is easier for a school of predatory fish to overwhelm and kill a person who enters the water, but because piranhas themselves are a link in the food chain for other larger species of fish. Being in a flock of dozens of individuals, the chance that you will be eaten is quite low.

Moreover, experiments with piranhas have shown that when alone, these fish do not feel as calm as if they were surrounded by other fish.

But despite their peaceful behavior towards humans, piranhas are real killing machines for other fish species that are lower than them in the food chain. Their powerful jaws are designed to bite and tear, and their dense, muscular bodies are capable of incredibly fast movements and jerks underwater. The piranha's jaw muscle contraction force relative to body size is believed to be the highest of any other vertebrate in the world. For example, the common piranha can easily bite off the finger of an adult.

But in history there has not been a single reliable case of a fatal attack by piranhas on a person. But this does not mean at all that these fish never bite a person or an animal that enters the water. And this behavior is almost always caused not by the aggressive behavior of the fish, but by self-defense or abnormal weather conditions, because of which the behavior of the piranhas begins to differ sharply from usual. Abnormal weather conditions mean a period of drought, when the rivers in which piranhas live dry up, and many fish remain in depressions filled with water, but cut off from the main channel, deprived of food. Starving predators gradually begin to eat themselves and may well rush at any creature that comes close to the water. Sometimes the tendency of piranhas to behave aggressively is recorded during the spawning period, when they rush at a person or animal in self-defense, but such cases are extremely rare. And of course there is no talk of a collective attack by piranhas on humans.

But all of the above does not mean that piranhas will refuse to eat human flesh. Unfortunately, sometimes tragic incidents occur on the water - people or animals drown. An already lifeless body floating in the water attracts many fish, including piranhas, which leave specific bites on it. People who see this think that the cause of death was an attack by piranhas - this is how most myths about attacks by flocks of piranhas on people or animals are born.

This is interesting: Suppose, in some unknown way, a huge school of piranhas of 400-500 individuals was driven crazy, and now they attack everyone who is in the water. For example, if this unfortunate person turns out to be an adult, then 500 piranhas will be able to gnaw him to the bone in 5 minutes!

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