There are more than 35,000 fish species in the world today, so it should come as no surprise that there are also deadly ones among them. However, when we think of deadly fish, we probably immediately think of huge sharks that can kill with one bite, but surprisingly, some of the deadliest fish are actually some of the smallest. Some fish contain enough poison to kill an adult in less than an hour – and not all of them have an antidote! Here we will discover the deadliest fish in the world, large and small.
10. Kandiru
Kandiru are small but deadly, measuring about 1 inch in length, and without a doubt they are a fish that should be avoided at all costs. They are freshwater parasitic catfish native to the Amazon Basin and are difficult to spot due to their translucent body. Candiru feeds on blood, they have a small head and body that can swell after eating. Although they usually live in the gills, larger fish are known to swim into the human urethra. Once they have entered the urethra, they are difficult to remove as they have backward-facing spines on the gills. Candiru then feeds on blood and mucous membranes and lays eggs in the bladder, which ultimately leads to death if not removed.
9. Tiger goliath fish
The goliath tigerfish is known as the most dangerous fish in Africa. These freshwater fish are found in the Congo Basin and are highly predatory, feeding on literally anything they can catch. The goliath tigerfish is incredibly intimidating with its large protruding teeth and is known as the African equivalent of piranha. In fact, the goliath tigerfish is the only freshwater fish in Africa known to actively attack humans. With the ability to reach a whopping 130 pounds, these ferocious predators often attack unsuspecting swimmers. Each tooth is about 1 inch long and you never have to worry about losing any as they even have a set of replacement teeth for those that have been lost or broken.
8. Velsky catfish
The Velsky catfish is a huge freshwater fish, reaching up to 16 feet in length. These giants are found in the lakes and rivers of Europe, and they are easily recognizable by their wide, flat head and huge mouth. The Velsk catfish feeds on worms, insects, fish, rodents, frogs and birds. Their mouths contain rows of small but incredibly sharp teeth, and there have been many reports of this fearsome fish attacking and killing humans, usually fishermen or unsuspecting swimmers.
7. Moray
Despite the fact that they look more like a snake, moray eels are actually fish and incredibly dangerous. There are about 200 species of moray eels around the world, and although most of them live in the sea, some of them are also found in fresh water. Most moray eels can grow up to 1.5m and lack the pectoral fins that some people mistake for snakes. Moray eels eat mainly squid, octopus, crustaceans and other fish. They often inhabit rocky crevices and they often attack divers. Moray eels are incredibly vicious when disturbed and attack with a lightning reflex. Their teeth are exceptionally strong and sharp, and they are bent back to prevent the victim from escaping. This makes their bites extremely painful and their wounds usually bleed profusely. Moray eels carry a toxin in the mucus and in the mouth that destroys red blood cells. This toxin is believed to be the reason why their bites are so severe.
6. Boxwood
The box fish is very similar to the puffer (next on our list), although not so deadly. Their size ranges from 10 to 24 inches, depending on the species, and they usually inhabit rocky and coral reefs in the Indian, Pacific and Atlantic oceans. They are distinguished by a box-shaped body and a honeycomb pattern on the skin. Boxwood mainly feeds on algae, worms and small fish, and they have an incredible defense mechanism to ward off predators. Through the skin, they release the toxin ostracitoxin into the surrounding water, which is toxic to everything nearby. This can be especially harmful to humans as it destroys red blood cells. In addition, some boxwoods are deadly if eaten raw. However, most people choose to avoid consuming them entirely due to their resemblance to blowfish.
5. Blowfish
Undoubtedly one of the most dangerous fish in the world is the puffer fish. There are over 120 species of puffer fish and they can range in size from 1 inch in length to over 2 feet. Pufferfish are found in most tropical and subtropical waters, and they swell into a balloon when threatened or disturbed, hence their name. They have large spines on their skin that are only visible when they are inflated. However, the fierce look is not their only weapon, as most blowfish contain tetrodotoxin. Tetrodotoxin is a powerful poison that is 1200 times more dangerous than cyanide. A strong poison is found in the liver, ovaries and intestines of blowfish, although even touching them is dangerous, and one fish contains enough toxin to kill 30 adults. What’s even more frightening is that there is no known antidote.
Fugu is also a Japanese delicacy known as fugu. Cooks must undergo rigorous training and special licenses before they are allowed to cook food. Even the slightest mistake can be fatal, and visitors are literally playing with death. The slightest amount of poison can cause paralysis and death, although the unlucky person is conscious until the end.
4. Great white shark
No list of deadly fish is complete without the great white shark. Great white sharks are the most famous sharks and are responsible for the largest number of unprovoked attacks on record. With roughly 300 teeth and an estimated bite force of about 18,000 Newtons, the white white is a fierce predator. The great white shark has an average length of 15 feet, but some reports have a record length of more than 20 feet, such as the “Deep Blue” great white shark, which is estimated to weigh 5,000 pounds! These incredible predators have an excellent sense of smell and can detect blood from a quarter of a mile away. Great white sharks inhabit the coastal waters of most major oceans and regularly eat fish, whales, dolphins, sea turtles and seals.
Many scientists believe that great whites do not deliberately attack people, but simply “taste test”. This is when they leisurely swim up to someone who often surfs and bite to see if they are edible. This is very different from when they deliberately hunt, fly up to their prey from below and deliver a crushing bite. Unfortunately for us humans, even a taste test can be fatal.
3. Oceanic whitetip shark
Oceanic whitetips are found in tropical seas around the world and are distinguished by their white-tipped fins. Although great white shark, tiger shark, and bull shark have far more recorded attacks on humans, it is believed that ocean white fin has killed the most people. This is because they often select survivors from shipwrecks and downed aircraft.
Oceanic whiteflies are best known for their attacks on survivors from US Navy ships during World War II. USS Indianappolis sunk 30th July 1945 from a Japanese submarine. Approximately 890 crew members were stuck in the water for four days, awaiting rescue. Only 316 survived. Survivors reported that about 150 people were killed by oceanic belcones, making this attack the deadliest shark in history. Oceanic whitetip sharks are also responsible for a large number of deaths when RMS Nova Scotia flooded in 1942.
2. Lionfish
Lionfish are incredibly venomous fish that live in the Pacific Ocean, although they have now invaded many other oceans. They reach about 18 inches in length and are distinguished by their vibrant colors. Lionfish may have red, white, or black stripes and have poisonous, pointed fin rays. They mainly feed on small fish and invertebrates and swallow their prey whole. Surprisingly, they bombard their prey with jets of water to confuse it before grabbing it. Moray eels and sharks are one of the few known predators of these fish. Their bites can cause severe pain, vomiting, and breathing difficulties. Although lionfish bites are usually not fatal to adults, they are much more dangerous to children, the elderly, or anyone with an allergic reaction.
1. Stone fish
The deadliest fish in the world is a stone fish that has serious the ability to harm!
Stonefish are 14 to 20 inches long and the same width due to their extremely wide pectoral fins. They inhabit tropical waters including the Indian Ocean, Pacific Ocean, Red Sea and Great Barrier Reef. Stonefish have hard skin and razor-like spines and contain enough toxin to kill an adult in less than an hour, making them the world’s most venomous fish. They are ambush predators that feed from the bottom of the seabed, where they camouflage themselves at the bottom. Their hard skin merges with stones and sand, hence their name.
The stonefish delivers venom through extremely sharp spines on its back. This is to ensure that they are protected from above when sitting on the seabed. Antivenom is available, but must be administered quickly, as paralysis and death can occur quickly. Surprisingly, their venom is just a defense mechanism, and stonefish don’t actually use it to kill their prey. Instead, they punch with their huge, powerful jaws and swallow their prey whole. Stonefish eat reef fish and small invertebrates. Sharks, rays and large sea snakes are their only predators.