Diving Milford Sound
“THE LAST FRONTIER” – Jacques Cousteau
Few visitors to Fiordland are aware that below the tide line there is another world with its own fauna and flora. Much of the uniqueness is caused by the light-absorbing fresh water layer. This restricts algal growth and allows deepwater or light avoiding species to become established in shallow water. Below this freshwater layer the sea water is calm, very clear, and relatively warm, with annual temperatures of 11-15 degrees centigrade: the smallest range anywhere on the New Zealand coast. This narrow temperature range throughout the year permits subtropical forms to exist. Black coral occurs in abundance in the waters of Fiordland from a depth of 5 metres. Red hydro-corals are found from a depth of 15 metres. The saucer sponge and the large tube anemone are common in water less than 20 metres deep in the fiords. Approximately 160 species of fish have so far been recorded by divers within the surface 45 metres of the fiords. These range from typically warm water, to cool water, to relatively deep water species. Warm water species include splendid perch and blue-dot triplefin.
