Discover a unique world beneath the waves.
The underwater environment in the fiords is one of the most intriguing and unique in the world. This is not only because of the beautiful natural environment and the marine reserves that exist here, but also because of an interesting effect of the high rainfall in the area.
As rainfall drains through the lush forests, it becomes stained with tannins until it is the colour of strong tea. This dark freshwater does not mix with the sea water of the fiords, but rather it sits on top, limiting the amount of light that reaches into the depths and restricting almost all of the marine life to the top 40 metres of water depth. This 40m band is calm, very clear and relatively warm - home to sponges, corals and fish of sub-tropical, cool water and deep water varieties.
As a result, light sensitive species that normally live at great depths are found much closer to the surface in Fiordland waters. This gives divers, as well as visitors to the Underwater Observatory, the opportunity to see rare species such as the red and black corals at relatively shallow depths.