Tiritiri Matangi Island, in New Zealand's Hauraki Gulf off the coast of Auckland, had just 4% of its original forest cover remaining by the time a revegetation programme began in 1984. Over the following decade, approximately 280,000 native plants were propagated and planted by an estimated 10,000 volunteers, raising forest cover to more than 60% and enabling the reintroduction of some of New Zealand's most threatened bird species, according to a 2013 study titled 'Tiritiri Matangi – an overview of 25 years of ecological restoration'.
Tiritiri Matangi: How 280,000 volunteer-planted trees rebuilt a New Zealand island ecosystem
Tiritiri Matangi Island, in New Zealand's Hauraki Gulf off the coast of Auckland, had just 4% of its original forest cover remaining by the time a revegetation programme began in 1984. Over the following decade, approximately 280,000 native plants were propagated and planted by an estimated 10,000 volunteers, raising forest cover to more than 60% and enabling the reintroduction of some of New Zealand's most threatened bird species, according to a 2013 study titled 'Tiritiri Matangi – an overview of 25 years of ecological restoration'.
From the mid-19th century, Tiritiri Matangi was progressively cleared for farming. Trees were felled, undergrowth removed, and the land converted to livestock pasture. By the 1970s, the island was a largely open, grassy outcrop with only scattered trees, and native birdlife had significantly declined.
In 1984, scientists from the University of Auckland, working with the Department of Conservation and community groups, proposed establishing Tiritiri Matangi as an 'open sanctuary' — a protected area where native species could be reintroduced and the public could visit.
Between 1984 and 1994, a revegetation programme planted thirty different native tree and shrub species. Volunteers organised into teams called the 'spade brigade' used pointed spades to plant seedlings. Groups typically numbered between 15 and 400 people per trip, each planting between 1,000 and 1,400 plants per visit. One group of 120 volunteers reportedly planted 2,000 trees in two hours. Early plantings focused on hardy pioneer species such as pōhutukawa, which could withstand exposed, windy conditions and later provide shelter for other species.
In the early 1990s, rats were eradicated from the island and strict biosecurity measures were introduced to prevent new predator incursions. The removal of introduced mammalian predators was carried out alongside the planting programme to create conditions suitable for native wildlife.
Following habitat restoration and predator eradication, native bird species were reintroduced. Species including takahē, kōkako, stitchbird (pōpokotea), saddleback (tīeke), and little spotted kiwi have been reintroduced to the island. Many populations are reported to be increasing, and the island now supplies individuals for translocations to other predator-free areas.
More than 30,000 people visit Tiritiri Matangi each year. Volunteers continue to assist with planting, monitoring, and maintenance. The United Nations Decade on Ecosystem Restoration (2021–2030) has highlighted Tiritiri Matangi as an official example of successful ecosystem restoration.
- No current population figures are provided for any of the reintroduced bird species.
- The specific biosecurity measures used to prevent new predator incursions after rat eradication are not described.
- The funding sources and total cost of the revegetation and predator-eradication programmes are not stated.
- The 2013 study cited as a source is not described in further detail, and it is not stated who authored it or where it was published.
- The mechanism by which the United Nations designated Tiritiri Matangi as an official example of success is not explained.
- No information is provided on how forest cover or bird populations have changed since 1994.
Read the original at The Times of India