Caring for ‘nature’s kidneys’
There is an old saying that ‘‘wetlands are the kidneys of the planet’’, so one would hope our wetlands were in good nick.
That way they would supply our drinking water, store our flood water, clean up our waste water, and return it to us fit for (re-)consumption.
Wetlands are also important habitat for a huge range of species, notably birds such as bitterns and crakes, but also fish, invertebrates, plants, and many organisms too small to see.
The extremely rare long-fin eel is fast losing its habitable wetlands due to dairy effluent. Swards of neinei or Carex secta are a thing of the past, allergic to pollutants such as hydrocarbons that have been washed off roads.
In Manawatu¯, we hardly have any wetlands left - only 3 per cent of the original surface area remains. Most have been logged or drained for agriculture.
Only tiny pockets of wetlands remain, and these are mostly disturbed - affected by drainage, weeds and pests.
As we cannot afford to pay the billions of dollars it would cost to use technology to do what wetlands do for free, we need to look after our wetlands, or they will decline further.
Wetlands are best looked after by protecting them from wandering stock, planting a belt of trees and shrubs around them as a buffer zone, restoring any lost aquatic plants such as flax, and leaving the water clean and undisturbed to provide natural habitats and services to all organisms.
Forest & Bird’s monthly gettogethers this year include talks on wetlands. On May 8, Professor Russell Death of Massey University’s Freshwater Ecology will talk about ‘‘The little things in our wetlands: a forgotten fauna in a forgotten habitat’’.
On June 12, Dr Phil Battley of Massey University’s Wildlife & Ecology Group, will talk about ‘‘Wetlands birds of New Zealand’’. Monthly talks are held second Tuesday of each month at 7:30pm at the City Library.
Lake Pauri, a small wetland near Kaitoke, south of Whanganui, which is full of water-filtering plants that lock up nutrients and other chemicals.