Complex sentence: Many of the dive sites are cave dives around the island; a wide range of marine life can be found, and common amongst it are moray eels, monk seals, octopus, and loggerhead turtles (caretta caretta).
Split into simpler sentences: Many of the dive sites are cave dives around the island. Further, a wide range of marine life can be found, common amongst being moray eels, monk seals, octopus, and loggerhead turtles (caretta caretta).