Diving with Bull Sharks at Bat Islands, Costa Rica

Costa Rica is a country famed for its abundance and variety of life, both animal and plant. A popular destination with tourists, the country prides itself on its pristine rainforests and eco friendly image. Sandwiched between the crystal-clear waters of the Caribbean, and the nutrient rich Pacific Ocean, the waters around Costa Rica are home to all kinds of aquatic life. Cocos Islands, some 500km off the coast, are frequently touted as one of the best dive sites in the world. loser to home the Pacific North West is quietly gaining popularity amongst the dive community. Local dive sites close to shore are impressive and diverse, but travel further from land, and there is something special tempting divers to this corner of Costa Rica – the chance to dive with Bull sharks at Bat Islands.


Diving at Bat Islands

Bat Islands (Islas Murcielagos) are a small group of uninhabited, rocky islands off the coast of Costa Rica’s Pacific coast line. Part of the Santa Rosa National Park, the waters here are a protected marine park, and patrolled by rangers. This has given marine life the chance to flourish in these nutrient packed waters. From macro life, to visiting pelagic species, Bat Islands offers you the chance to experience world class diving in Costa Rica. You cannot actually set foot on the islands, as it’s just a rocky outcrop. Whilst you are almost guaranteed to see some amazing underwater life on your dive trip to Bat islands, the biggest draw for many is the chance to dive with the majestic Bull Sharks.




Bat islands diving
The boat ride out to Bat Islands

Getting to Bat Islands

As Bat Islands are uninhabited, your only chance of reaching them is by boat. The Aggressor runs liveaboard diving trips to Bat Islands. If that is a little out of your budget then do not fear, as Bat Islands can easily be dived as a day trip. There are several dive operators dotted along the coast of Guanacaste, including in Playa Del Coco, Ocotal and Flamingo. These centers will frequently run day trips to dive Bat Islands during May – November.  These are the best months for spotting the Bull Sharks at Bat Islands. Off season, waters become rough, visibility reduced, and the weather unpredictable.

Enjoy the journey!

I spent 6 months in Costa Rica and had the pleasure of diving Bat Islands several times. The journey out there can be a memorable experience too. During my 1 hour boat trip from Playa Del Coco, I frequently saw dolphins and turtles on the way to the dive site. Humpback whales also migrate along the coast, and it is not uncommon to see them breaching or slapping their tails. The weather can be unpredictable, and winds can pick up quickly. If you are prone to sea sickness I would suggest you take precautions and prepare yourself.

The Big Scare

There are a few dive sites around Bat Islands, but the most well known is the “Big Scare” which offers a high chance of diving with Bull Sharks. Whilst the name suggests that there may be something sinister going on, there is no reason to fear being around the beautiful Bull Sharks. The first time I dived here, I was so overwhelmed with excitement, as I saw the unmistakable outline of a chunky Bull Shark in the distance. The site itself is actually not so interesting, in that it is just a gradual sloping stony bottom.


Generally, you will follow a dive master who will head to around 30 metres and then slowly make their way shallower in a zigzag pattern. During the dive everyone should swim slowly and look in all directions. Prepare yourself for the fact that this is nature, and nothing is guaranteed. The best thing about bat islands is that these Bull sharks are undisturbed and have never been fed or baited. This means humans are not upsetting their natural habits. If you know you will be disappointed if you dive Bat Islands and don’t see any sharks, then I suggest contacting the dive centers and asking if there have been many Bull Shark sightings recently.



eagle ray bat islands
Eagle rays at Bat Islands

Bull Sharks – aren’t they dangerous?

If you do manage to strike it lucky and find yourself diving in the company of Bull Sharks, then don’t be scared. This species is often given a negative press, but there are no known accidents involving Bull Sharks and humans at Bat Islands. I found that on the occasions that I encountered these sharks, they would often circle the divers from afar. There are some destinations in the world where people feed the sharks, or lots of divers get very close. This changes their behaviour. Here in bat Islands, there are very few divers, and absolutely no feeding of the sharks happens. They do not naturally want to hurt humans, and we are certainly not their source of food! In fact, when I have encountered them, they have been rather shy. For your best chances of not scaring away the Bull Sharks, you should stay low and move slowly.

Black rock dive site – Bat Islands

A day trip to Bat islands often involves a dive at Big Scare, followed by a dive at Bajo Negro (Black Rock). If you were not lucky enough to catch sight of Bull Sharks at Big Scare, then you can at least look forward to the diving Black Rock, which never fails to disappoint. A huge rocky pinnacle that juts out of the water, this dive site is absolutely teeming with life. You will often find yourself surrounded by huge schools of fish such as jacks or spade fish. Resting down on rocky ledges you can often see white tip reef sharks or nurse sharks. As you circle your way around the pinnacle, you should slowly ascend as to not pass you no decompression time. Taking a torch can be handy, as there are often Moray Eels and Octopus hiding in crevices. Sightings of Eagle Rays are common. You can never quite predict what animals you will encounter whilst diving at Bat Islands, but I have heard first hand stories of Pilot whales, Orcas, False Killer whales and Manta Rays. As your dive draws to an end, it will be time to head away from the rocks and make your safety stop in the blue. Several times here, I have heard the tell-tale whistles of nearby Whales and Dolphins.



Manta Ray Costa Rica
Manta Rays are often spotted at Bat Islands

Who can dive at Bat Islands?

Diving at Bat Islands is certainly not for beginners. Due to depths, an advanced diving certificate is needed. You may even consider going one step further and get certified as a Deep Diver as the Bull Sharks are generally found around the 30 metre mark. Currents can be strong, and visibility varies greatly. Generally, boats cannot anchor and so divers are dropped close to the islands. From there, it is a quick descent before everyone drifts apart. Consider getting a refresher or doing a local dive before tackling Bat Islands if it has been a while since your last dive. It will certainly make the dive more enjoyable for you.

What equipment do I need to dive with Bull Sharks?

I would recommend taking a computer and SMB as a bare minimum, which could possibly be rented from your dive centre.  If you are feeling a bit rusty on how to use the Surface marker Buoy, then do ask for some pointers. Currents here can easily drag you away from the group and Divemaster, meaning you may surface alone and need to make yourself seen.  Due to the depths that the Bull Sharks like to frequent as Bat Islands, a computer will help you stay within your No Decompression limits, although there is nothing to say you can’t use the tables! Also be aware that temperatures in the water here can vary greatly, and thermoclines are very common, so make sure you have enough protection. Dive Centres in Playa Del Cocos will have 3mm suits to rent, but anything thicker can be harder to get hold of. If you know you are someone who feels the cold to an excessive degree (I hold my hands up to this!) then you may feel much more comfortable in your own suit!

You may want to also bring an underwater camera. Don’t use strong strobes and flashes as that will only scare the Bull Sharks. Also it is worth noting that Pacific water here at Bat islands is quote dark and there can be a lot of particles in the water. I most certainly would not recommend any kind of noise maker as they too wil just scare he sharks, and subsequently annoy any divers!

Prices for a 2 tank dive trip out to Bat Islands start at around $160.

Final thoughts…

Diving at bat Islands is certainly a bucket list experience for divers. It is a more affordable alternative to Cocos Island, and still relatively quiet in terms of tourists. Bat Islands is unique in that it really is one of the only places where diving with Bull Sharks is a very real possibility, even though they are not fed or baited. Fpr the time being, Playa Del Coco remains relatively quiet and not swarming with tourists, so there is no time ike the present to get out and visit the Bull Sharks. If you find yourself in Costa Rica, then make the time to dive at Bat Islands – you wont be disappointed!

Looking for a general info on diving in Playa del Coco? I write all about it here!

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One thought on “Diving with Bull Sharks at Bat Islands, Costa Rica

  • January 23, 2018 at 2:07 am

    That’s super cool to see the bull sharks face to face – gosh, must be quite shocking as well 😀


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