Fiordland National Park is one of the largest national parks in the world. Extremely hard rock has been carved out by glaciers during ice ages, leaving steep faces which much of Fiordland's forest clings to.
Most of Fiordland is covered in dense beech forest with an under layer of ferns, lichens and mosses. Growing above the bush line are snow tussocks and many species of low growing alpine plants such as daisies and buttercups.
Fiordland is home to many native birds including some unique flightless species, which have been on the brink of extinction - for example Kakapo and Takahe. The introduction of stoats, deer, rats, possum, and mice has had a devastating impact on the native bird populations. Fiordland National Park is home to several initiatives aimed at the reduction of these predators. Some off shore islands in the park, after intense work, are now pest free, and native species have a safe haven to strengthen their populations.
The fiords are also home to some unique marine life.
Rain draining through the bush into the fiords becomes stained with tannins. This forms a dark brown layer that doesn't mix with the sea water. Because of the colour, light doesn't reach down to the depths, and most of the marine life exists in this band of fresh water. Species that would normally live at great depths are found much closer to the surface, giving divers the opportunity to see rare species and beautiful black corals.
Many species of sea birds and marine mammals thrive in the fiords including Bottle-nosed and Dusky dolphins, whales, fur seals and 2 species of penguin.