Kettle Holes
A kettle hole is a bowl-shaped hollow in the loose rocks that have been left by a melting glacier. When a melting glacier moves back, large blocks of ice are left behind. These blocks of ice are covered in outwash. When the ice blocks melt, kettle holes are left behind.
Swamps
Swamps get their water from streams, ground water or run-off.
Bogs
Bogs get their water from rainwater. They are often found in alpine areas.
Ephemeral (temporary) tarns
- small mountain lakes that are sometimes dry
- the plants are called turf-vegetation and look like a thick carpet
- they are used by water birds
- they are often made by a kettle hole
The table below shows photos of the same ephemeral tarn. It is a good way of seeing how the tarn changes during the year.
March |
April |
early May |
mid May |
late May |
August |
November |
|
Photos courtesy of George Iles
Ashburton Lakes
- there are 12 lakes in total
- they were formed by glaciers
- the four main ones are Lake Heron, Lake Clearwater/Te Puna-o Taka, Lake Camp/Otautari, and Lake Emma
- Lake Heron is the largest lake and is an important place for some endangered birds.
Braided Rivers
- the Rangitata River is a braided river
- braided rivers break into many strands (called braids)
- the braids change over time
- the Rangitata was formed by a glacier
- the Rangitata River carries stones down the valley
- braided rivers are great feeding and nesting grounds for native birds.