South America: The most dangerous animals

The WorldTravelerApart from cute exotic animals, less popular species also cavort in Latin America. Although they can become dangerous, they enrich the fauna of the huge continent just like all other animals.

Encounters with dangerous spiders, for example, are not rare: Keep your nerves because these poisonous crawling animals like to show their aggressive side.

From the highly poisonous Terciopelo fer-de-lance to the swinging rattlesnake – many dangerous snakes also provide adrenaline rush. To experience constrictor snakes, you don’t have to go all the way into the jungle. The Anaconda, for example, can already be found on the outskirts of Brazilian cities.

Comb spider

You really don’t want to run into the already mentioned comb spider: It belongs to the most poisonous and aggressive spiders on earth and does not behave very „spider-typical“, which makes it even more unpredictable. The up to five centimeter long greyish-brown specimen is often confused with the less dangerous tarantula – with often deadly consequences.

Instead of building nets in a corner, the comb spiders wander around on the ground in search of prey and also like to make themselves comfortable in shoes and clothing. If they feel threatened – and this happens very quickly – they jump at the supposed attacker from a short distance or even run after him. If they have caught „the enemy“, they often bite several times.

The bite is followed by almost unbearable pain, accompanied by dizziness, impaired vision, pulmonary oedema, fever, cramps and breathing difficulties, etc. The tissue is quickly destroyed by the poison, and in the past limbs had to be amputated. The bite can also lead to death in humans if the Phoneutria immune serum is not administered within twelve hours. In the worst case, the victim dies of respiratory paralysis after 12 to 17 hours.

The crested spiders are mainly found in South and Southeast Brazil and Northern Argentina on plantations and in gardens, but also in the Amazon region and in Central America.

Great Anaconda

There are many myths surrounding the giant boa. Allegedly, animals weighing 450 kilos and 30 metres long have been sighted. One thing is certain: Even if this is perhaps exaggerated, you should not get too close to this impressive constrictor. Although it has no fangs, it is all the more powerful: the anaconda waits for its prey in the water, bites and suffocates it by wrapping itself tightly around it. Then it eats the animal (for example rodents, fish, caimans, small deer or even capybaras) with the head first and in the whole, which can take many hours.

The Anaconda is one of the largest snakes in the world and is at home in the tropics of South America – mainly in swamplands, still and slowly flowing waters. It can be found all over Brazil, for example, where it even dares to venture right up to the gates of the big cities. Typically, the Anaconda moves in shallow water, but sometimes hangs in branches to dry.

These giant snakes are not yet well researched, but it is known that females are on average much larger and heavier than males. The latter can reach a length of up to three to four meters; the females are at least twice as long and weigh considerably more kilos. One animal about nine meters long has even been caught.

Several males are often involved in the mating process, all of which simultaneously embrace a female and form a „mating ball“. After six to eight months the Anaconda gives birth to between 18 and over 70 offsprings, depending on size.

Terciopelo fer-de-lance

This easily irritable viper is responsible for many poisonings with subsequent limb amputation as well as numerous deaths. The dangerous snake lives in the tropical rain and deciduous forests of Central and Northwest South America and can also be found on sugar cane plantations, along riverbanks, in tree hollows near villages and even in people’s homes, where it is not uncommon for it to have unpleasant encounters with the fer-de-lance.

The snake, which is about two metres long, is particularly dangerous for people, because they often notice it too late. The snake does not flee when people are approaching, but remains motionless. If you get too close or touch it, it bites immediately. It straightens up and bites with its long fangs in the area above the knee. Large quantities of her toxins enter the body in seconds; it is not uncommon for a survivor to have his leg amputated.

The tissue-destroying toxins of this snake from the subfamily of pit vipers are very complex and have not yet been sufficiently researched. The bite is followed by nausea, vomiting, palpitations, painful lymph node swelling, internal bleeding, etc. In the meantime, antidotes have been developed, but only an experienced physician should judge which antiserum is administered to the patient in which dose, for example to avoid allergic reactions.

The nocturnal viper feeds mainly on small mammals such as mice and rats, but also on lizards, birds and frogs. It gives birth to its offspring – around 80 young – alive. The snakes can live up to 20 years.


Statistically speaking, Brazilian beaches – after Australia, South Africa and the USA – are in fourth place worldwide in terms of the number of shark attacks. Especially in the state of São Paulo and in the northeast of the country (e.g. Maranhão and Pernambuco), incidents with predatory fish (e.g. the bull shark) occur more frequently.

At Recife’s famous 20-kilometer-long beach „Boa Viagem“ (also called „Copacabana of the Northeast“) in the elegant residential area of the same name, there are so many shark warning signs in the sand that one does not even like to go into the water anymore. The beach had gained sad fame with 50 shark attacks, 19 of them deadly, between 1992 and 2007. Today the situation has eased due to the many security measures.

Mostly the human being himself is responsible for the (often changed) behavior of the sharks, who look for new food sources after the destruction of their habitat. For example, the shark attacks in Recife are directly related to the destruction of the coastal mangroves and the expansion of the deepwater port in the 1980s. Among other things, the construction had the consequence that the current conditions in the river mouths changed, the prey fish of the sharks were displaced into the bathing region and as a consequence of the increased shipping traffic more waste was discharged into the sea, which in turn attracted sharks.

In other areas of South America, too, caution is advised regarding sharks. The dangerous bull shark is not only found in the coastal waters of Ecuador, Colombia, Venezuela and Southern Brazil, but also in freshwater, e.g. in river estuaries or in the Peruvian and Brazilian Amazon – up to more than 4000 kilometres upstream.

The notorious great white shark is not only found in the coastal areas of Brazil, but also off Uruguay and Argentina. The shark does not mind cooler water, as it is able to keep the temperature in some parts of its body ten to twelve degrees higher than that of seawater. The tiger shark, just as dangerous as the bull shark and the great white shark, likes it a little warmer and lives, among other things, in the tropical and subtropical waters off the coasts of South America.

In addition, there are other shark species that are also at home in South America, but are less aggressive. With a little caution, however, unwanted encounters with all sharks can be avoided (e.g. you should never go swimming in murky waters, early in the morning or in the evening hours and in any case ask the locals on-site if and where it might be dangerous).


The jaguar is one of the most dangerous, but also most impressive animals of South America. For centuries, the indigenous peoples have worshipped this magnificent, proud cat of prey, which can kill its prey with a single blow of its paw. Thus, in the religion of the Maya, the god of the underworld appeared in the shape of the jaguar; with the Aztecs, the supreme warlords wore jaguar skins and were called „jaguar warriors“.

The third largest cat of prey in the world (after lion and tiger) lives in large parts of South America – mainly in the rainforest, bush land, savannahs and high grass – always with water nearby. Although the jaguar can weigh up to 125 kilos and its physique looks stocky, it moves smoothly and is a very good climber.

In contrast to the leopard, its little brother from Africa, the dark circular spots in the yellow to reddish-brown fur enclose even a smaller spot. If the coat is completely black, the jaguar is called the „black panther“ (like leopards with black coloring).

The jaguar, after often having waited in ambush for a long time, hunts down its prey quickly and effectively: First it sneaks up on its prey from behind, then it kills it after a short spurt with an enormous paw stroke – or at least tears it to the ground. After a bite to the neck or skull, even the toughest opponent is dead.

The jaguar’s meals are generally quite varied, as he eats just about anything that moves: snakes, caimans, fish, lizards, frogs, armadillos, tapirs, sloths, deer, birds, monkeys and larger mammals. He also does not stop at turtles. Every now and then he gets a pet, which makes him quite unpopular with the farmers. But the habitat of the jaguars is more and more restricted by the deforestation of the rainforest, so that unpleasant encounters with humans are not to be avoided.

Poison dart frog

These frogs from the South and Central American rainforest shimmer in the most beautiful colors. But one should not be deceived by their attractive appearance: some representatives are among the most poisonous frogs in the world; their brightly colored outfits serve as a warning to their enemies to stay away from them.

If hungry jungle dwellers nevertheless attack one of these frogs, they quickly regret it: the convulsive poison „Batrachotoxin“ paralyses muscles and breathing; a person can die within 20 minutes from a dose of 0.002 milligrams per kilo of body weight.

However, as a tourist, the probability of encountering these frogs in the wild, for example, is extremely low. And there are only three species where the encounter can be fatal, for example the terrible poison dart frog („Phyllobates terribilis“) from Colombia. If its strong poison penetrates the human body through a skin wound after contact, the hours are numbered.

The „Phyllobates bicolor“ and the „Phyllobates aurotaenia“, also from Colombia, are in no way inferior to their brother in terms of danger. These three are responsible for the name „Poison Dart Frog“, which the entire family bears. Because with their nerve poison, some indigenous peoples of western Colombia prepared the tips of their blowpipe arrows before they went hunting.

Many others of the more than 200 poison dart frog species are less poisonous and cause „only“ nausea, gastrointestinal problems and fever on contact. But tree climbing frogs do not have to be poisonous in principle: Only when eating poisonous prey do they absorb the poisons and accumulate them in their bodies. If they live in captivity and are not provided with the appropriate food, they lose their poisonousness and usually give birth to non-toxic offspring.

Red piranha

True horror stories are circulating about the piranhas. In 1914, for example, US ex-president Theodore Roosevelt wrote in „Through the Brazilian Wilderness“: „They tear apart and devour alive every injured person and every wounded animal, because blood in the water makes them furious.“ Others even went so far as to describe the predatory fish with their sharp teeth as „man-eaters“.

However, as we now know, only some species are dangerous, for example the red piranha, which occurs mainly in the Amazon and Orinoco basins, but is also common further south to the Rio Paraná. Normally the hunter, which is about 20 to 25 centimetres tall, eats mainly fish and crustaceans, but is nevertheless one of the most aggressive freshwater fish in the world. Although there are hardly any known cases of people being killed by piranha attacks, one should never swim in piranha waters alone or with a bleeding wound. Especially in the dry season, when the predatory fish live closely packed together and start eating each other, it can be dangerous.

Indeed, whole swarms of piranha are attracted by just a few milliliters of blood in the water, because blood usually means easy play with an injured animal. The attack very fast: First the victim is fixed, then bitten and with a shaking movement the piece of meat is torn out of the prey. The animal then bleeds to death. To swallow, the piranhas remove themselves from their prey. In the end only bones remain.

Since they are resistant to many diseases and even have carrion on their menu, the piranhas in the Amazon region make themselves very useful as health policemen: they eat not only sick animals, but also carcasses that float in the water en masse during floods. In this way, they ensure that no epidemics spread in the sensitive ecosystem.


The shower rattlesnake Crotalus durissus is up to 1.80 metres long and is not the only rattlesnake south of Mexico. It is also the most poisonous representative of its species.

But the whole thing can be topped: The most southerly of its subspecies, Crotalus durissus terrificus, has a reputation as the most venomous rattlesnake ever. Three quarters of its bites end deadly within a very short time if left untreated, as it is mainly nerve poisons that act on the central nervous system and lead to shock, paralysis, kidney failure, but also to permanent blindness.

This highly poisonous snake lives in large parts of South America –
from southeast Peru to the Brazilian Atlantic coast and down to southern Argentina. It eats mainly rats, birds, small reptiles and mice. Its young are born alive.

The poisons of other show rattlesnakes should not be underestimated, but do not necessarily end deadly, because the bites are easily treatable. The toxins can often cause tissue destruction, swelling and local pain. However, those affected are often saved by medical help and the appropriate antidote, which is less the case with crotalus durissus terrificus.

If you want to protect yourself from rattlesnake bites, it is best to wear high shoes and keep your eyes open when hiking. Rattlesnakes do not flee from humans and sometimes sunbathe in the middle of the path. Another danger comes from dogs that find the snakes in the bushes. If you hear their rattling, you should stop immediately, locate the rattlesnake and then walk slowly backwards out of the danger zone.

Black caiman

With a length of over six metres, the Black Caiman occupies the top position among the largest predators in South America. No wonder, then, that the reptile has been immortalized in several books – albeit in less flattering roles, e.g. in Matthew Reilly’s bestseller „The Temple“, in which Moor Caimans constantly eat people who have fallen into the water.

This largest of all South American crocodiles lives on river and lake shores and in flood plains of the Amazon basin, in Brazil’s northern state of Amapá and in French Guiana. The reptiles are not called „black caimans“ for nothing, because they are dark coloured and have a lighter head. The males were hunted for a long time because of their beautiful leather.

Although the nocturnal black caimans make a rather sluggish impression, they are fast on the water and on land. Before its swimming prey (e.g. capybaras, birds, lizards, other caimans and mammals) has realized what is going on, the crocodile is already on the spot and drags its victim into the depths to drown it. Despite the fact that there have probably been only a few attacks on humans so far, tourists should stay away from the banks, especially in the evening hours in crocodile-rich areas, and certainly not jump carelessly into the water.

Common vampire

The name is no coincidence, because this bat species has a lot in common with the bloodsucking creatures of the night. Thus the Common Vampire feeds on (animal) blood, which is unique among mammals. Humans fear him less because of his blood thirst, but rather as a carrier of dangerous diseases like rabies. Many have been infected by vampire bites.

These bats are not particularly demanding in their choice of habitat and are at home in the South American tropics and subtropics up to altitudes of 2400 meters. They even swarm through the night on the Venezuelan island of Margarita.

Their social behavior is quite astonishing: They not only clean each other’s fur, but also feed hungry conspecifics with blood that they have previously choked up. Without this animal helpfulness, it is estimated that more than 80 percent of the common vampires would die each year, and that they can survive on average only a few days without blood.

The animals bitten are mainly mammals such as cattle, donkeys and horses, but also game and large birds. The Common Vampire approaches his victim jumping, then picks out a hairless spot on his body, salivates it – which has a numbing effect, shaves feathers or hair away with his teeth, bites out a piece of skin and then licks the blood out of the wound. Afterwards he is often almost twice as heavy, so that he can hardly manage to take off. The bitten animals are often infected, Thousands of animals die of plagues or other diseases caused by vampire bites every year.

South America: The most exotic animals »