The 9 Most Dangerous Animals in Japan: Predators & More!

And When you think Japan, you might well think of Tokyo and Osaka. Bustling cities of industry and modern technology. The only animals you might even consider are the ones served up on beds of rice with pickled ginger. But we are here to tell you that, yes, there are a tonne of animals living in Japan. And not all of them have the best reputation. That is why we have unearthed for you the top nine most dangerous animals in Japan! And there is sure to be at least one curve ball in there, we assure you!

Join us as we talk teeth, claws, stings and venom. We will uncover which beasts are lurking for you to worry about. And which, if any, can be called a predator. Let us answer those burning questions; what is the smallest animal or insect to worry about? And what can we do to avoid these creepy critters? Rest assured, you will leave us armed with all the best knowledge about how and where to find and avoid the most dangerous animals in Japan.

Top 11 Most Dangerous Snakes in Thailand

japanese forest
Photo by pcowell on Envato Elements

Japanese Keelback Snake

The keelback snake is a great one to start with, because of their interesting biology. There are a number of different species of the Rhabdophis genus of snake, but not all are venomous. Or indeed Poisonous. It is rare to have species of venomous and poisonous snakes in the world. But in Asia and Japan, the keelback is one of them!

Venom is made inside the glands of the animals body, and has to be delivered directly via bite etc to be dangerous. Poison, on the other hand, can be transmitted through the skin and/or organs. This makes poisons very dangerous indeed! The keelback snake in Japan is venomous yes, but it has also been known to ingest poisonous frogs, storing the deathly liquid in the glands at the base of its skull. Often, they will bare this part of their neck when attacked so as to deliver a jet of poison into the mouth of the would-be diner. This deters them, and can even kill them. the snake can then escape unharmed.

The 7 Most Deadly Snakes in India: The Bad & The Venomous

The species of Japanese keelback will have diamond shapes along its back in varying darker colours of black, brown and green. Found in the lower parts of the country, like Honshu and Kyushu, they love to hide in grasslands, forests, crop and rice fields. They’ve also been spotted in the surrounding Japanese islets. If you find yourselves in these locations, be sure to wear ankle protecting hiking boots! Whilst the poison wont harm you, the venom they inject is known to be very painful and even debilitating. Anti-venom is widely available however, just ensure you get to a hospital as soon as you can. You might also hear them referred to as Kamikomu.

dangerous animals japan
Photo by Jan Kubita on Unsplash

Redback Spider

Some of the most dangerous critters in Japan aren’t actually from the continent. You might also know this one as the black widow from Australia, which came over in cargo ships some years ago! The earliest reports of redback spiders in Japan were 2009, though reports in 2014 in Tokyo showed numbers on the rise. to date, however, there have been no known fatalities.

Most people by now will be familiar with the venomous bite of the redback spider, and how they like to hide in the worst places. Like in boots and under your toilet seat! If you are unlucky enough to cop a bite, symptoms can include nausa, sweating, vomiting, abdominal pain, and even hypertension. Again, the prevalence of anti-venom means you can seek help from a hospital and are extremely likely to pull through.

Spiders in Thailand: We Show You 5 Creepiest Crawlies to Avoid

This doesn’t stop their reputation for being little hell beasts though. Just spotting one can make the skin crawl. They’ve also been known eat small reptiles like lizards and snakes, as well as spiders and flies that get caught in its web. Gruesome!

dangerous animals japan
Photo by Jonatan Lewczuk on Unsplash

Japanese Wild Boar

Whilst these guys can look like friendly little warthogs, watch out! They can, and will, gore you with their horns if you get in their way. And this can be fatal! Earning its place amongst the most dangerous animals in Japan. Wild boars are notoriously aggressive, and not afraid to attack humans if they feel provoked to. Even if you are minding your own business. Angry and bulky as they are, boars are omnivores who dine on vegetation, bugs, grubs, lizards. Even sometimes carrion. 2018 saw reports of villages being overrun by wild boars as they attacked unattended rice paddies, and slept in abandoned buildings.

You will find boars all over Japan, except in the Hokkaido and Ryuku islands. Though usually you will not find them inside of the cities, except on your plate! Seriously, there are some interesting wild boar recipes you can find online. Something to think about if you find yourself on the business end of a wild boar attack. Revenge is a dish best served… cold, hot? Take your pick.

dangerous animals japan
Photo by Jonathan Kemper on Unsplash


Speaking of dinner⁠—this one gets the prize for the most amount of people killed after its death! Belonging to the Tetraodontidae family, the pufferfish is the notorious deadly dinner. This does not stop it from being a national delicacy in Japan, however. If you see ‘Fugu’ on the menu, be warned. That is pufferfish. But why is it so deadly, you ask?

The pufferfish contains a power substance called tetrodotoxin, making it both disgusting-tasting and lethal to would-be aquatic predators. Unsurprisingly, it is also extremely lethal to humans! It is so poisonous that one pufferfish could kill around 30 people. It is said to be more dangerous than cyanide. And, perhaps worst of all, there is currently no cure.

Also Read  7 Dangerous Animals in Morocco: Most Deadly Wildlife

9 Dangerous Animals in Fiji to Avoid (Biggest Fiji Killers)

But this doesn’t deter the adventurous diner! The fish is very difficult to gut correctly so as to avoid the toxins, so it must be prepared by highly trained and licensed chefs. Even so, there are deaths reported every year from ingesting the toxin by accident.

Some say that the taste is slightly like chicken, whilst others say that it has a subtle taste of gelatinous white fish meat. Either way, it is sure to be so highly sought by those who like to live dangerously. Would you give it a go?

dangerous animals japan
Photo by Brian Yurasits on Unsplash

The Habu Snake

The Habu or protobothrops flavoriridis genus of pit viper is known for its temper and large striking range. However, it is mainly nocturnal and can be only be found on the Ryukyu islands, to the south of Japan’s main islands. So one that can be avoided easily Interestingly, this is one of the only forms of pit viper that produces eggs, rather than giving birth to live baby snakes.

If you intend to visit these islands one day, be sure to look out for the Habu snake! The telltale signs are the light brownish or olive body, covered in dark green or brown wavy splodges. An adult can grow to between four and five feet long, and is known to homes in search of small rodents to eat. If you come across one, avoid at all costs!

Snakes in Mexico: The Good, The Bad & The Deadly

If attacked, the Habu snakes venom is not entirely lethal, but potentially very damaging. It contains a mix of cytotoxin and haemorrhagin, and whilst anti-venom will stop the spread, some victims have reported the loss of motor-function after treatment, and even permanent disability. Other symptoms that can arise from a snake bite of this magnitude are vomiting, nausea and hypotension. And of course, if left untreated, death. This is definitely one to memorise before visiting the islands!

dangerous animals japan
Photo by mostafa meraji on Unsplash

Japanese Mountain Leech

Perhaps you have heard the tales of yore, where quacks would prescribe leeches for maladies. Interestingly, leeches are still prescribed as an alternative treatments to improve bloody flow! But this is one leech you do not want to introduce to a patient.

Known as the Yamabiru, these creatures are silent suckers. As terrestrial beings, they live on the ground, rather than in water. They crawl into the socks of the unwitting to feed, and you don’t feel it. The mountain leech grows to ten times their original size after feasting on your blood. Granted, they’re only around 1.5cm in length to begin with. But we promise you at 15cm leech in your sock is not for the faint of heart. Plus, they look so much worse than a standard leech!

These guys wont kill you necessarily. Though being fed on by a bunch of them while sleeping would severely deplete your blood supply by morning! Luckily these are more pervasive in rural areas. Perhaps not one of the most dangerous animals in Japan, but certainly one of the more unwelcome!

dangerous animals japan
Photo by SeDemi on Envato Elements

Japanese Mamushi Snake

Last up for venomous snakes, we have the Mamushi snake. It also goes by the very cute name of the Japanese Moccasin, though it is definitely not cute by nature! This is perhaps the most dangerous in our list of animals in Japan. They can be found across the main islands and surrounding archipelagos in fields, forests, swamps and marshlands. Luckily, not so much in cities, though we wouldn’t rule it out.

Yes, this is another form of pit viper common to Japan. the head is slightly wider than its long body, with large diamond like shapes arranged along a pale canvas of red or yellowish brown. The Mamushi isn’t the largest, with an adult growing to between 1 and 2.5 foot, but its venom can really cause some damage.

Are There Snakes in Hawaii? The Good, The Bad & The Friendly

Similar to the Habu, one bite can wreak some serious havoc if left untreated for too long. Severe reactions include necrosis of the skin and muscle degeneration as the tissues liquify. Other victims have reported psychosis. This is due to the presence to two types of neurotoxin in the venom.

Generally, the mamushi snake likes to prey on small mammals, reptiles and insects. As an ambush predator, however, it can often camouflage itself amongst leaves and undergrowth, lying in wait for its victim. This is when a human could fall foul of it, so be mindful of this when walking in nature.

The 6 Most Deadly Snakes in Bali

dangerous animals japan
Photo by Fernando Santander on Unsplash

Asian Hornet

When it comes to insects, this is certainly not one to underestimate! Also known as the Japanese giant hornet, this is the worlds largest hornet. And so it is pretty easy to understand why it should be so feared. Small wasps and hornets are scary enough. Plus, they have a time honoured tradition of getting right up in everybody’s grill. You will be able to spot an Asian hornet because it looks like a souped up wasp. Light orange body with brown stripes across it abdomen, legs and antennae. Known as Oosuzumebachi in Japan, or ‘great sparrow bee’, adults grow to around 4cm long!

The good news is that the Asian hornet isn’t particularly deadly. The venom it contains, however, is very potent and can cause long term damage to the surrounding area. Plus, the sting reportedly feels like being jabbed with a hot poker. It could, however, kill a person through anaphylactic shock. So, if you know you are allergic to bee stings, be vigilant.

Another reason to fear these hornets is their ability to kill of vast swathes of the bee population in a very short time. Almost thirty thousand in around an hour! In 2019, the Asian hornet or ‘murder hornet’ was reportedly seen in the Pacific Nortwest of the USA. This seems to have died down, however, with no further reports in the news. We are hoping things stay this way. Do not confuse this with the related yellow legged hornet, which causes issues across Europe.

Also Read  7 Best Luxury Hotels in Bodrum Turkey: 5-Star Resorts

dangerous animals japan

Ussuri Brown Bears

We are saving the most fearsome wild animals to last! Arguably one of the most dangerous animals in Japan, albeit not quite so pervasive. This bear looks and acts rather like the grizzly bear of the US and Canada, and is found in the Hokkaido region to the west of the Ishikari area, and also the Teshio-Mashike mountains. Sadly, it is the deforestation and areas of farming lands that robs them of their natural habitat. This could be a reason for the reported attacks on humans.

The 9 Most Dangerous Animals in Colorado to Watch Out For

Interestingly, the Ussuri brown bear is not technically considered a ‘predator’ as it is mainly a herbivore. However, its size and stature make it a fearsome foe if you decide to cross a hungry bear, or mother with cubs! Whilst there have been some reports of females and her cubs approaching fishermen and playing nearby without incident, the Ussuri is responsible for the worst bear attack in Japanese history. this was back in 1915 however, there have no been too many reported attacks in recent years.

Similarly, the black grizzly or ‘Asiatic black bears’ also native to Japan, should be one to watch out for. These have been known to attack when threatened, or when food is scarce and they are hungry. However, they are mostly omnivores, preferring to eat fruits and nuts, as well as small mammals and insects. They have also been called the moon bear and white-chested bear, and are present as spirit guides in Japanese folklore.

Whilst these bears should absolutely be feared, the biggest takeaway should be the sad fact of their habitat being destroyed. Most biologists would say that the bears would rather avoid us, but they are often victims of circumstance. And if you ever come across a bear in the wild, just know they probably have smelled food on your. So chuck the food and when they chase it, escape!

dangerous animals japan
Photo by Joshua J. Cotten on Unsplash

Are there any predators in Japan?

A predator is anything that naturally preys on its living food. Predators come in many forms, from mammals to reptiles. And yes, Japan is full of them! They predominantly take the form of smaller mammals and reptiles that live away from cities in forests and grasslands. Though there are some larger beasts in our list of the most dangerous animals in Japan.

When thinking about predators, ones mind naturally lingers on the larger mammals with big teeth and claws. Lions and tigers and bears, oh my! But do you have these to fear in Japan? Well, lions only hail from mainland Africa, and so you aren’t likely to see them in Asia unless in a zoo. On the other hand, you can certainly uncover many hairy (pardon the pun) stories of encounters with bears. You may well find them lurking in our run-down of the most dangerous animals in Japan! But what of the enigmatic tiger? Surely there will be some lurking in the forests of Japan?

dangerous animals japan
Photo by USGS on Unsplash

Are there Tigers in Japan?

With tigers appearing so much in Dynastic art, you would think that there most certainly are. In fact, tigers are not native to Japan at all! Often imported to the nation and given as gifts before the end of the 19th Century, they became a household image, and a symbol of beauty and freedom in Japanese lore.

They do slink solo through the Siberian woodlands, and over the perimeter of the northeast of China, however. It is thought that early artists drew inspiration from pelts brought back by travellers. The rest they got from common house cats! In fact, there are only two larger wildcats you will find in Japan. The first, the cute looking leopard cat, which can only be found on the Tsushima archipelago, off the northeast tip of Japan. It can also be found on Asian mainland. The second, the Iriomote cat unique to its namesake, the Iriomote island. This is located to the southwest of Japan, very close to Taiwan.

So, if we wont find felines on our list, just which animals await us on this list of the most dangerous animals in Japan?

dangerous animals japan
Photo by Nick Karvounis on Unsplash

What is the most dangerous animal in Japan?

You might think, the larger the animal, the more fearsome. But in this case, you would be wrong. The Asian hornet is widely accepted to be the most fearful being in Japan! The Oosuzumebachi or ‘great sparrow bee’. Whilst the sting wont necessarily kill you, the toxin it delivers can cause massive issues to the skin tissues. It can also cause untold damage to the nervous system.

Aside from this, the hornet is known to be very aggressive. If provoked or angered, the insect will chase you down and deliver its potent sting. And if you provoke a nest, well. This could definitely prove fatal. The lesson here is to always stay away from hornets, especially when in Japan!

Bby now you should feel armed with the knowledge to take Japan by storm. No longer will you need to stick to the big cities. You can wander the towns and villages fully aware of what to do and how to avoid or deal with these beasts. A good rule of thumb is, when stung or bitten, seek anti-venom. Also, if you see a bear bribe it with food and run!

Share this with your fellow intrepid explorers and start planning that trip to Japan. There is so much more to see than the cities. Perhaps you could even start a friendly game of dangerous animal bingo!


James Ardimento has spent the last 12 years journeying around the globe ! With its precious experiences and tips he gained around Asia, South America, Europe and the US he is a precious asset for this blog and for its readers