Champagne Vent Garden

Hydrothermal CO2 vents on the sloping seafloor south of Pointe Guignard release streams of warm bubbles that rise through coral formations, giving the site its champagne name. Water directly over active vents reaches 40 to 50 degrees Celsius at the source, cooling rapidly in the surrounding column, and the temperature differential creates a shimmering thermocline effect visible to the naked eye. The altered chemistry around the vents creates unusual coral growth patterns that marine biologists use to study ocean acidification analogue conditions. Parrotfish, damselfish, and chromis are abundant on healthy hard coral, and the shallow depth — rarely exceeding 18 metres — makes this an excellent second dive or night dive site.