Scuba Diving The Bat Islands in Costa Rica


The Bat Islands are one of the most impressive scuba diving destinations in all of Costa Rica. The Bat Islands (or Isla Murciealgo in spanish) are located on the Pacific Coast of Costa Rica off of the northern province of Guanacaste. They are actually located just off the coast of Santa Rosa National Park, which is famous for it’s landscape, wildlife, as well of some famous surfing spots such as Witches Rock and Ollies Point. The area is protected as a marine reserve by Costa Rica and for this reason has its populations of fish and marine animals protected from fishing. Some of the marine life that you are bound to see in the Bat Islands are huge schools of fish, several species of turtles, large schools of rays, whales and dolphins depending on the season, and most famous atleast for divers of the area are the encounters which we have with the highly impressive bull shark!

Bull Shark Diving At The Bat Islands Costa Rica

Bull sharks can be found year round at the Bat Islands, however, most trips and most sightings take place from mid May until early November.  Diving at the Bat Islands is most famous for the encounters which are quite often had at a dive site called Big Scare with bull sharks. This dive site is located just off the tip of the last island in the chain and for whatever reason is frequented by a fairly large population of bull sharks. This dive is generally just for divers who have atleast their advanced certification and there are several reasons for this. First, the dive can be fairly deep. Depending on the conditions, visibility as well as where the sharks may be, we often reach depths of up to 100 feet on this dive. We also can encounter quite strong currents at depth. These currents can come on at different points in the dive and are fairly unpredictable, so we always prefer to have experienced, skilled, and confident divers. Another skill which you could be asked to do at the Big Scare is a negative descent. Quite often there can be surge at the dive site which makes it very beneficial to drop in quickly and reach the calmer water which is found once you get down 15 or 20 feet. We do this by doing a backroll of our ribbed inflatable boats with no air in our BCs and then regrouping at depth before starting the dive.

At the Big Scare the big attraction is the bull shark, however, it is a fairly common to spot the Giant Pacific Manta at this site as well as huge schools of jacks, and other fish, eels, and rays. The visibility at the site is highly variable and can range from 15-90 feet. Generally, the better conditions will exist in the green season in Costa Rica from mid May until November.

Black Rock

Quite often your second dive at the Bat Islands will be done on a dive site called Black Rock. This dive site is a large pinnacle which appears a km or so offshore of the mainland of Costa Rica and comes straight up from 80 feet or so to reach just a few feet above the high tide mark. This pinnacle provides a home for seemingly endless schools of fish. Dropping in on one side of the rock, you will descend into swarms of fish which can fully engulf you. You will spend the whole dive to make a full 360 degree rotation of the pinnacle. At the end of the dive if you have air and time left, quite often it is nice to swim off into the blue for your safety stop which can sometimes result in seeing completely different species and schools of fish. This is a dive site which never disappoints!