Bat Islands bull shark dive

Divers make this run for bull sharks up to about three and a half metres long. The Islas Murciélago are a scatter of five islands and ten islets at the far outer edge of Santa Rosa National Park, roughly 45 km northwest of Playas del Coco, and the boat ride out across open sea takes a little over an hour. Dolphins and turtles often show up on the way.

The sharks are seen from May to November, mostly at a site called Big Scare (Gran Susto). This is not a trip for new divers: depths run from about 18 to 35 metres, the current and surge can be strong, visibility swings a lot, and a cold thermocline sits around 18°C. Dive shops take only experienced divers who are used to depth and current. Manta rays, eagle rays, big schools of jacks and the odd whale shark turn up too.

The day has three dives. Boats leave early in the morning and get back around mid-afternoon, and some dive boats from Coco collect divers straight off the beach at the Papagayo resorts.