Kōrero: Wetlands

There is a serenity to wetlands – a still lagoon, the lonely call of a bittern, rushes stretching to the horizon. They may be less dramatic than some New Zealand landscapes, but they are home to many land birds and rare species, and they are vital for sustaining healthy waterways. Six are now listed as having international importance.

He kōrero nā Peter Johnson
Te āhua nui: Canterbury marshland painted by W. Menzies Gibbs

He korero whakarapopoto

Ngā whakaahua me ngā rauemi katoa o tēnei kōrero

What are wetlands?

Wetlands are areas where water gathers – as a swamp, or just boggy ground. Some wetlands merge into lakes, or into drier ground nearby.

Varied wetlands

New Zealand has a lot of rain, which produces wet soil. There are also many different landscapes, so there is a wide range of wetlands. In some you can see water, but in others it is below the surface. Some swamps may form in winter and spring, but dry out altogether during the summer.

Two common types are swamps and bogs.

Swamps

Swamps occur in basins, valleys and plains. Often there is water above ground (it wells up from below), and the soil is quite fertile. Common plants are sedge, rush, reed and flax. New Zealand’s biggest swamp is Whangamarino, by the Waikato River.

Bogs

Bogs lie on flat or gently sloping land, and get their water from rain. The soil is peat, which has few nutrients and poor drainage. But trees, ferns and other plants can grow there. New Zealand’s largest wetland is a bog known as Kopuatai Peat Dome, on the Hauraki Plains.

Plants

From forests to tiny mosses, several plant groups can cope with wet sites. Examples include kahikatea (New Zealand’s tallest tree), mānuka, flax, raupō (bulrush), and cushion plants, which grow in small mounds.

Wildlife

One quarter of the native land birds use wetlands for food and breeding. You can often see pūkeko, ducks and white-faced herons. Shyer birds – rails, bitterns and fernbirds – stay hidden.

Other wildlife includes eels, mudfish, frogs, dragonflies, moths and snails.

Importance of wetlands

Wetlands are important because:

  • they have many native plants and animals, some endangered
  • they keep water flowing, and reduce the impact of floods
  • their plants improve water quality.

Since humans arrived (1250–1300 AD), about 87% of the wetlands have been lost through farming, drainage and other activity.

People and wetlands

Māori found fish, birds and edible roots in wetlands. They made cakes from the pollen of raupō. They used flax for weaving, and dried moss for bedding.

Today, thousands visit wetlands around the country to walk, fish, hunt and study nature.

Me pēnei te tohu i te whārangi:

Peter Johnson, 'Wetlands', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/mi/wetlands (accessed 20 April 2024)

He kōrero nā Peter Johnson, i tāngia i te 24 o Hepetema 2007