The Dollabarat Reef is a shoal situated 5 km (3 nautical miles) south-southeast of the Formigas Islets. The reef is named after Pierre Dollabarates, the Basque captain who accidentally discovered the reef when his small boat was destroyed after grounding on it on 7 March 1788. Dollobarat Reef is part of the Formigas Islets Nature Reserve, which provides protection for the reef. The strong currents, deep waters and presence of sharks make diving difficult for those not familiar with open-ocean diving.
There is a rich pelagic community on and around the reef, with large numbers of jack, stripped barracuda, Atlantic bonito and grey triggerfish present. Large oceanic predators like manta rays ( Mobula birostris ), sicklefin mobulas ( Mobula tarapacana ), Galapsgos sharks ( Carcharinus galapagensis ), and the shortfin mako ( Isurus oxirhyncus ) are often seen in the area. Large number of demersal species such as groupers, dolphins, pilot whales and loggerhead turtles are frequently observed.
The shallow reef, at 3 m below the surface, is believed to be unique in the Azores and is covered in a dense and tall cover of Cystoseira spp , called chainbladder kelp. Cystoseira is found mostly in temperate regions of the Northern Hemisphere and is prevalent throughout the Azores. The fronds of Cystoseira are generally 20-30 cm long and provide shelter for a large number of fishes, such as juvenile ornate wrasse, emerald wrasse, and juvenile dusky grouper. Cystoseira depend on good water quality, and can be used as bioindication of the health of a reef.