Over the last 160 years, the area of wetlands in the Waikato Region has declined by around 75 percent. Many of our remaining wetlands are being invaded by introduced pests. Despite the losses, our Region is still a wetland stronghold and home to three internationally important wetland sites. 
Wetland facts
Between 85 and 90 percent of New Zealand’s wetlands have been lost. In the 1840s an estimated 110,000 ha of wetland covered the lower Waikato area and Hauraki Plains. Since European settlement, many Waikato wetlands have been drained and converted to pasture.
Current estimates of the area of remaining wetlands in the Waikato Region are around 32,000 ha (25 percent of what we had). This figure includes Whangamarino (7,100 ha) and Kopouatai Peat Dome (9,200 ha). Check out the area of wetlands in 1840 compared with today on our Wetlands in the Waikato Region map.
About 80 percent of our remaining wetlands are in lowland areas in the Waikato, Matamata–Piako, Hauraki and Franklin Districts. Check out our map showing the percentage of the Region’s wetlands in each district.
Check out our indicator on the extent of wetlands in the Waikato Region.
Areas of international significance
The Waikato Region is a New Zealand stronghold for wetlands. We have the two largest freshwater wetlands in the North Island, the country’s biggest river delta, and around 30 percent of the nation’s remaining wetlands1.
Some of our wetlands are listed on the International Convention on Wetlands of International Importance (Ramsar sites). There are only five Ramsar sites in New Zealand. Three of them are in the Waikato Region:
Our wetlands are also home to many plants and animals that are found nowhere else in the world. Find out more about our wetland plants and animals.
Changing habitats
Habitat loss and the isolation and fragmentation of wetlands have led to a decline in many wetland plants and animals. Many wetland plants and animals are now threatened with extinction.
People’s activities in and near wetlands can cause changes, such as lowering the water table and increasing the amounts of nutrients in the soil and water. These, in turn, can cause changes in the vegetation (for example, the replacement of native sedges with willow). Willow is now the dominant wetland plant in the Region.
The table below lists the area of different wetland vegetation types remaining in each bioclimatic zone.
Area of each freshwater wetland vegetation type (hectares) by bioclimatic zone
| Vegetation class |
Nutrient level |
Coastal (< 1 km from the coast) |
Lowland (below 100m) |
Sub –montane (100 to 300m) |
Montane (above 300m) |
Total |
| Raupo |
High |
13 |
16 |
353 |
– |
382 |
| Flax |
Med/High |
– |
3 |
697 |
– |
700 |
| Shrub/sedgeland |
Med/High |
153 |
5,803 |
1,048 |
11 |
7,015 |
| Kahikatea forest |
Medium |
– |
150 |
– |
– |
150 |
| Willow |
Med/Low |
22 |
10,297 |
518 |
– |
10,837 |
| Sedgeland |
Med/Low |
74 |
3,138 |
797 |
– |
4,009 |
| Peat bog |
Low |
– |
6,722 |
– |
– |
6,722 |
| Total |
|
262 |
26,129 |
3,413 |
11 |
29,815 |
Find out about restoring a wetland.
Footnotes
- Based on a national estimate of approximately 100,000 ha in Ministry for the Environment and GP Publications. 1997: The State of New Zealand’s Environment. GP Publications, Wellington.