Dangerous Animals

Please see why you should come and visit Costa Rica

Created: 2000.05.04 | Last updated: 2020.09.07


Every place in the world I’ve been there are animals that can kill you. In most places, humans are the most dangerous ones. This page talks about the next most dangerous ones.

Canada first

When chatting with Costa Rican’s – they were terrified of the Grizzly and other bears we have back home. I hike in the mountains every month, and though I have come across Grizzlies and other bears, I know how to act around them and have never had a problem in any encounters (note: There is no solution for polar bears other than avoidance). I’ve also come within feet of black bears (they are black, brown and light tan colored) many times and have never had a problem – again, you just know the rules. I had one Tico (the name Costa Rican’s give themselves) in Sámara and Nosara, Guanacaste asked in terror and sincerity if we all carried guns and shot bears on sight – I asked: do you carry guns and shoot crocodiles whenever you see them? He got the point.

Note: if you visit my area of the world and you are going into bear country – don’t be cavalier, make sure you know and follow the rules, bears are indeed dangerous. Tourists get out and try to feed them and the bear doesn’t know where the food stops and your arm starts. Tourists try to put their child on the back of the bear for a photo, too much reading Winnie the Pooh. Tourists pull the bear’s ear to try to get them to ‘look at the camera’. Locals don’t do any of those stupid things.

In my part of Canada, Elk and Moose are the most likely to kill you even though I have encountered far more bears, and there are virtually no problems with people who don’t act stupid with bears.

We also have snakes - there is a den where many Rattle snakes near where my twins live in Lethbridge.

Now Costa Rica

In Costa Rica, I’m told Crocodiles (Cocodrillos, similar to Alligators, but I’m told Crocodiles are more aggressive) and snakes are your ‘big’ worries, and more for children, Anacondas in the water. In addition, all sorts of bugs including no-see-ems, ticks (lyme disease), mosquitos and other bugs are your ‘little’ worries.


I’m not an expert but what I understand is: When at a river, look up and down for anything bumping out of the water, then take a stick and hit the water to see if anything moves. If it does, don’t go in. That handles the Crock and Anaconda problems.

Poisonous and other snakes

To be fair, I don't want to get bitten by a snake, poisonous or not!

For poisonous snakes – don’t go in grass unless it is cut low – simple, just don’t do it. I’ve heard there is on average 1 poisoness snake per hectare (about 1 per acre) so Let the locals, who know more details, take their snake stick and a machete, and then, when the grass is low, you go. If you insist on ignoring this, make sure you are wearing high hiking, cowboy or work boots that a snake can’t bite through*, take a snake stick and machete with you – and follow a guide and his or her instructions in detail.

You need a 17 or 18″ high boot, ideally that is designed for this, and make sure you understand the statement: “That a snake can’t bite through.” Standard cowboy boots, especially the fancy dress ones for example are not that thick, you need a pair that are designed for snake bite prevention.

When you see a bunch of tourists by a river in Costa Rica, chances are they are looking at a crock. Don’t feed the crock - it won't know where the chicken ends and your arm begins! If you MUST ignore this – stay back 10 or more meters (30'). I do not know if 10 meters is safe enough – crocks can move very fast. But 10 meters (10 yards) seems safer than 1 meter (1 yard). If you want to compare this to my home country: If a bunch of tourists are stopped on the highway, they are probably feeding a bear or putting their children on the back of the bear for a 'horsey ride'.

the overhyped, dreaded, bullet ants

Have you heard about bullet ants? Ants whose bite feels like you were hit by a bullet? I have not been hit by a bullet or bit by a bullet ant so I can't really compare, but this is one animal you don't want to come in contact with. Fortunately, it is very unlikely you will run into this animal unless you decide to be foolish and take unreasonable risks. I also don't know anyone who has been bitten by a bullet ant, or anyone that knows anyone who has been bitten by one, this includes several friends and collegues who have lived years in Costa Rica, several their whole life. I'm told they are large and beautiful. They are fairly docile and do not typically sting a large animal. Don't put your hand in their nest (base of trees). I've seen a video of someone who purposely got bit/stung for video reasons. He said quite calm that it is a very painful sting, and that it gets worse over the 1st thirty minutes then starts to fade. I'm not going to try it.

To avoid them, first be aware of whether you are in Bullet Ant territory: Deep rainforests. You will have a guide - the guide will be making sure you don't come in contact as long as you don't rush out in front of them.

Beyond that, the same advice for snakes applies to these ants, so - just don't stick your feet or hands in places you can't see.

If you are really lucky, you will get to see a bullet ant. If one crawls on you, don't panic! - just like bees in Canada in won't sting you unless you do something stupid like threaten it's home or crush it. So ... don't crush it - if you crush it, it is much more likely to sting/bite you. If you are lucky enough to see a lot of bullet ants, stand back and watch the birds come for some dinner.

You won't see them at all in the Sámara and Nosara/Prados Del Sol area, but if you are in an area where they are prevalant, I'm told they will sometimes as a swarm swoop through your house, they won't touch your food, but they will clean out all the other insects - dead or alive and then leave. You WANT them to. And they are daytime ants, so don't worry about being surprised while you sleep at night.

Similar to many other stings, applying rubbing alcohol once or twice on the sting location can take away the sting in a few minutes.

little pests like mosquitos, ticks and so on

For many little pests … use a DEET or Picaridin based insect repellent, if you are on the Caribbean coast (Malaria*), sleep in a mosquito net. Grab grab a tube of ‘stop itch’ from Wallmart before you leave Liberia (we tried – we never found it anywhere else, not even in the aeroporta.) Skip the home remedies and Amway lotions etc.., DEET is one of the safest, most tested chemicals ever and it is the only effective deterrent for Mosquitos etc..,

there is NO risk of Malaria

2019 Update, I understand that there is no risk of Malaria on the Caribbean coast either. It was 2008 that I was told that there was a risk. So either it was just a fear that it was getting to close in Panama or it is no longer a problem. My source of risk then and now: Canadian Blood Services.

the ONLY 3 effective mosquito repellants

DEET: (mosquitoes, ticks, some flies) Maximum protection is achieved at 30% DEET formulations—higher concentration levels simply make your protection last longer but it takes a lot higher concentration to get any significant increase, so better to go with 30% and reapply after 8 hours. Controlled-release formulas, though, which include just 20 to 30 percent DEET, provide protection for up to 12 hours.

Picaridin: (mosquitoes, ticks, flies) Maximum protection is provided in formulations with 20 percent picaridin. Spray versions protect for up to 12 hours against mosquitoes and ticks, and up to eight hours against flies; lotion formulations last for up to 14 hours against mosquitoes and ticks, and up to eight hours against flies. While, as a chemical, Picaridin hasn't been around as long as DEET so there are some reasons to be suspicious of it long term - it has been around now for decades, so personally I trust Picaridin safety wise as much as I trust DEET (Which means I have no fear of either.) The big advantage of Picaridin over DEET is that it doesn't feel as greasy. So when it works, I prefer it.

In Canada (Southern Alberta) in 2020, Pidcaridin was only 50% effective against insects. In 2019 it was just as effective as DEET. So I switched to DEET. I figure ... best to have both DEET and Picaridin. I've never yet had DEET not work, but I prefer Picaridin when it works - non-greasy.

And netting Physically stopping them from getting access works too! Some notes though:

  • one tiny crack in the netting, especially if you do it on a bed, and you can assume they will get in.

  • Skinny jeans give mosquitos the perfect landing spot - they can suck your blood THROUGH the jean material and most other clothing. Anything that is tight against your body is a risk. I wear a belt as the only tight spot, but still occassionally get stung on my sholders (where my shirt is 'held' up.) The looser the clothing, which is also good for the heat, the fewer bites you are likely to get.

In the water

If swimming near coral, don’t touch it, lots of little nasty things there, and the coral can scrape you up pretty badly even if you don’t get stung or bit by something. (I received 2 stings when swimming too close to coral in Costa Rica once, painful ‘poison’ for 5 minutes, then for 10 minutes an hour later, other than that it was just the ‘physical’ non-poison pain, it healed easily, but others have not been so lucky. My wife once stepped on a spiky anemone or urchin in Jamaica – sore for a week.)

Sharks are not normally a concern, but if locals or signs tell you that sharks are around - don't be stupid, stay out of the water. And if you see a shark, my understanding is the best solution is to calmly, slowly, swim away without splashing.

ohhh - what a pretty frog

Don't touch any colorful frogs. Poison!

In general around the world, what I've learned is "brightly colored equals dangerous."

Sumary of risks, don't panic!

If you want to know what the risks are: I’m told that Mosquitos attack humans the most (but no serious illnesses). As far as serious problems ... Crocks have the greatest frequency of human attack – stupid tourists feeding the crocks chicken feet is the number 1, poisonous snake bites is number 2 and vending machines falling on you is number 3. I’ve heard the following from several sources, it doesn’t make it true: that you are more likely to be killed having a vending machine fall on you than to be killed by a shark. I’d still slowly swim away if I saw a shark, but I don’t avoid vending machines, well, not because I'm afraid of them falling on me, I avoid them because their contents are expensive and I'd prefer to have some of the fresh Costa Rica food over a vending machine sandwich! Of course if you spend your whole life in and near the ocean, and you always stay uphill and at least 2 meters (6′) from any vending machines, then I guess the shark risk will be higher.

what if you get sick (from a big animal or the really tiny virus and bacteria types)?

If you do get sick from something in Costa Rica, get treated there, don’t return home first. This is a general rule around the world in every country I've travelled, each hospital knows both the symptoms and treatments for local health risks better than anywhere else in the world – and Costa Rica starts out as one of the top world health centers to boot. This is advice I’ve had from Canadian doctors throughout the years (I’ve traveled extensively around the world) – if you get sick, get diagnosed and at least start your treatment before you return, then bring your diagnosis with you.

Be aware that some treatment you cannot have at home. For example, I have a friend who had a form of Malaria that there was only one treatment - Heroin. His malaria flared up about every 7 to 9 years, and he was travelling in the USA when it flared up. He carried a prescription for Heroin with him - but in the USA it was illegal. He was dying. His family ended up having to get 'street' Heroin. The only delay was it took hours for his son to convince a street dealer that he wasn't a cop! A few hours later my friend was doing fine and was discharged - the doctor said "See, we TOLD you he didn't need Heroin to recover." They said nothing and got on the next plane back to Canada. Fortunately, most diseases don't flare up repeatedly (I guess technically Malaria isn't a 'disease', it is a parasite.) Anyway, my point is, get treated in whatever country you get sick, then if you aren't fully cured by the time you leave, try to take back instructions that can be carried out when you get back home.

Above all, Don't panic, take sensible precautions and enjoy any country you are visiting including the ones with dangerous animals like Canada, USA and Costa Rica.

I hope most importantly that none of this scares you away from coming to Costa Rica. Every country has it's risks, as I've touched on a couple times above, in Canada we have more mosquitos than Costa Rica, we have black/brown bears (relatively safe), grizzly bears (less safe), polar bears (they make grizzly bears seem tame), mountain lions (aka cougars) that will stalk you, especially in British Columbia, wolverines, horseflies (ouch), wasps, bees, buffalo and elk - even deer are dangerous if they decide to gore you instead of runnig away. So to my mind, Costa Rica is no more dangerous, just different dangers.