
A comparison of plant species at Karori Sanctuary with similar sites in the Wellington region and with early herbarium records has helped us to determine which native species should be reintroduced.
Lower lake wetland
As freshwater wetlands are rare in the Wellington Ecological District it is important that the Sanctuary accommodate as many appropriate wetland species as possible, to provide the diversity of habitat needed for aquatic fauna to establish.
While there are a few wetland plant species naturally occurring in the Sanctuary, ongoing management is required to improve habitat diversity. Plant propagation for restoring and enhancing wetland areas has been a major undertaking.
Eight key species of wetland (riparian) trees and shrubs have been planted in the upper and central freshwater stream habitat zones. They include cabbage tree, tree fuchsia, swamp maire, kahikatea and pukatea and they have been planted to enhance the stream habitat. Exotic species such as buddleia and pampas are being removed to restore the habitat to a more natural state.
Grasses, sedges and rushes form the most important component of wetland flora in the Sanctuary. They have been planted in large numbers around the lake edges and lower lake wetland. The 28 species identified for planting have been chosen because they are representative of a typical Wellington wetland and are important for wetland fauna. Key species include toetoe and kakaho (similar to toetoe).
An underwater survey of the lakes in 2002 shows that both lakes support a healthy and diverse cover of native vegetation, with only a few exotic species. Removal of the exotic species is not regarded as a priority because there would be continued reintroduction by waterfowl, and it appears that no artificial enhancement of native species is required.
© Karori Sanctuary