In 1987 the first
takahē were introduced to the island. A ranger from DOC lives on the island, which has its own native plant nursery, electric generator and boat shed. The DOC staff haul their boat out of the water up a ramp with a winch. Some structures on the island provide habitat for native animals; for example,
little penguins roost under the old
woolshed.
Habitat restoration program are visible. The restoration program has been characterised by a high level of community involvement, led by groups such as the
Royal Forest and Bird Protection Society of New Zealand, the
Friends of Mana Island, tramping clubs and school children. This effort has resulted in it being selected as one of the top ecological restoration projects in Australasia by the Global Ecological Restoration Network. Seedlings from a radius of the island are brought to the plant nursery where they are raised until ready for planting out. Although over half a million native plants have been established under a planting programme, two-thirds of island will remain in grass and coastal shrublands. Planting has been mostly in gullies and sheltered parts of the island, which experiences strong winds. The strategy has been to plant native shrubs in connecting corridors. This suits most bird life and allows for natural regeneration. The plantings have been mainly of hardy pioneer species best able to withstand the rigorous conditions. When there has been enough shelter established, the forest area will be inter-planted with a variety of less robust species to establish a typical Wellington coastal forest.
Animals The island is a scientific reserve holding many native animals and plants that are rare on the mainland. Notable species on the island include the
Cook Strait giant wētā,
shore plover,
North Island robin,
takahē,
Wellington green gecko,
yellow-crowned parakeet, and
brown teal. The most recent example is the critically endangered Wellington
speargrass weevil from the Wellington South Coast in 2006. The Department of Conservation and the Friends group also collaborated on a five-year program to establish the threatened tūturuatu / shore plover on the island. The birds, of which only about 200 remain in the wild, were sourced from a captive population at the
Pūkaha / Mount Bruce National Wildlife Centre. A rat exterminated the population in 2011 and another attempt at reintroduction in 2020 failed after attacks by a
kārearea/New Zealand falcon. Mana Island was formerly home to translocated
kākāpō. After the kākāpō recovery plan was established in 1995, one of the first actions was to move kākāpō to the island. The last two males found on
Stewart Island were moved to the island. Both of the males released onto the island died, suggesting that the island may not be suitable for the kākāpō. However, the birds were also at an extremely light weight when moved to the island, which might have been a factor. Planned projects include the transfer to the island of a wide range of other species, many of which are rare and endangered. Notable amongst these will be the
tuatara, the
little spotted kiwi, a subspecies of the carnivorous
Powelliphanta snail, and a range of threatened plants endemic to the
Wellington Region.
Seabirds Recent projects have included the successful translocations to the island of
diving-petrels,
fairy prions and
fluttering shearwater chicks, with the progeny of several transferees later successfully fledging – the first to do so on Mana Island for many centuries. These species are an important part of the restoration of the island because of their nutrient inflows (free fertiliser) and the habitats their burrows provide for reptiles and
invertebrates. The seabird translocation techniques perfected on Mana Island are being used with rare and endangered species elsewhere in New Zealand, such as the
Chatham Island taiko,
Chatham petrel and
Hutton's shearwater.
Gannets formerly nested on Mana Island. From 1998, after mice were eliminated, conservationists have attempted to restart a colony, using a false colony of birds made of concrete, and installing sound systems that make gannet sounds, in the hope that real ones will be attracted to nest there. A male gannet, nicknamed
Nigel, arrived in 2015 and over the next two years courted one of the concrete decoys. A second male gannet, nicknamed Norman, resided on Mana Island during 2017. In January 2018, three gannets settled on the island. In February 2018, Nigel died. The same combination of techniques is showing good results in a similar project at
Young Nick's Head, near
Gisborne. ==Geology==