of private, Crown or Māori land may be leased back by the Crown under conservation covenants to preserve the natural environment. Conservation areas The Department of Conservation administers several types of conservation areas under the Conservation Act 1987: Conservation parks are a group of 54 areas protected for their natural and historic resources, and for public use, covering an area of . They include 36 forest parks that predate the 1987 legislation. Wilderness areas are areas of land managed for preservation of indigenous natural resources. Buildings, machinery, livestock, vehicles, aircraft, roads and tracks are banned in these areas unless it is for a specific management, scientific or safety purpose. Ecological areas are areas managed for the protection of the particular values of that area. There are currently 112 areas such areas, most being wetlands around Ōkārito Lagoon on West Coast. Sanctuary areas are areas managed to preserve indigenous plants and animals in their natural state and for scientific and other similar purposes. Watercourse areas are areas of land protected under the Conservation Act, Reserves Act or QEII National Trust Act, which are next to inland waters also under some form of protection. In each area, both the land and waters have outstanding natural or recreational characteristics. Amenity areas are areas managed for protection of indigenous natural and historic resources, and for public recreation. Wildlife management areas are areas managed for the protection of wildlife and other indigenous natural and historic resources. Examples include Matatā Lagoon, Kārewa / Gannet Island, and Moutohorā Island. Marginal strips are barriers of land adjoining the sea, lakes or rivers. They are protected for conservation, the maintenance of waters, water quality, aquatic life, protecting natural values, and ensuring ongoing public access. Stewardship areas are areas managed to protect the natural and historic values, which can be disposed of through a public process if retaining the land wouldn't "materially enhance the conservation or recreational values of adjacent land". Other conservation and administrative land, including certain types of state forest land, private or Māori land protected by the Minister of Conservation, and land held by the Department of Conservation for offices or visitor centres. Ecological islands The Department of Conservation and private trusts operate a number of ecological islands as protected habitats for endemic and native New Zealand species: Island reserves are areas set aside by the Government covering 220 off-shore islands. Mainland islands are areas of the