Eco-restoration
Why Consider Quail Island for Ecological Restoration?
Quail Island is much drier in summer than islands off the North Island, such as Tiritiri Matangi and Mana, where forest restoration is successfully underway. Not only is Quail Island drought-prone but it lacks streams or springs. In these circumstances unassisted forest growth is likely to occur at a comparatively slow rate and mainly during especially wet years. Nevertheless, the success of the 1982 plantings shows that restoration to woodland can be achieved in a few decades.
Quail Island is only semi-isolated. At extreme low tide mudflats are exposed, connecting the island to the mainland. This could make it accessible to rabbits and to mammalian predators such as stoats, ferrets and cats. The presence of these animals could hinder the reintroduction of flightless or ground dwelling birds, such as weka or robin. It seems likely that forest restoration will be more difficult than in wetter climates, and that rabbits and their predators could cause ongoing problems.
Why go to the trouble of attempting ecological restoration of Quail Island?
Here are some reasons:
An opportunity to Increase local biodiversity
The attractiveness and beauty of the natural world is enhanced by its variety. Most of us enjoy these qualities. Moreover we have a responsibility to maintain diverse assemblages of native plants and animals. They are part of the Aotearoa heritage which should be passed on to future generations.
In the last 150 years Banks Peninsula and the Christchurch region have suffered tremendous losses of fauna, including bats, bird species, lizards and many invertebrates. Many birds and mammals have been introduced from overseas, and they have added vitality to what would otherwise be a species-poor pastoral and garden landscape. However the losses of native fauna outweigh any gains. For many complex reasons, the loss of goal species diversity can reduce the ability of ecosystems to recover from natural and human-made disturbance. If the natural healing mechanisms of the planet are interfered with, our own survival is threatened.
Finally, native organisms have an intrinsic right to exist. Unfortunately the majority are unable to live in habitats made up almost entirely of plant cover, such as occurs in our planted parks, timber lots, gardens and farms.
To encourage native birds, extensive and diverse areas of native plants are needed; they provide the necessary food for invertebrates and birds.
By restoring coastal forest to Quail Island we will be helping to preserve and enhance local native plant and animal diversity in a relatively small, but important way. Some of the rare plant and animal species of our region may ultimately be able to thrive there and to be made accessible to all who wish to see them. Development of woodland will create many microhabitats which will be suitable for small native herbs and ferns, as well as mosses, liverworts, lichens and fungi.
For almost all land animals, the plants which form their habitats must be the first concern. The chief emphasis here is on woodland planting, but maintenance of areas of open, low cover such as grassland, as well as areas of bare ground, will be important for some animal species (e.g. lizards, invertebrates). Invertebrate animals of many kinds-worms, molluscs, crustacea, millipedes, spiders and insects will find suitable living places both in woodland and grassland.
The Need for Mainland Habitat Island and Inshore Islands for Conservation
Many of the remaining native forest birds in Canterbury and in the rest of New Zealand occur mainly in protected areas. The larger forest reserves are often found in difficult environments, for example in the mountains and on distant offshore islands that have harsh climates and thin, infertile soils. Diversity was relatively high in the native lowland habitats, but these are now all strongly modified. The most productive lowland forests survives, life for plants and animals is difficult. Food resources are often limited, restricting reproduction and making animals vulnerable to predation and disease.