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Results Forum News 33 article: Ridding Tristan da Cunha's outer islands of alien plants Purpose Complete removal of an alien plant and its propagules (seed bank), with a known ability to spread invasively throughout the vegetated area of Gough Island. Benefits will accrue indirectly to a number of communities: domestically to the people of Tristan da Cunha, in that the 40% of their territory which is protected as nature reserves and as a World Heritage site will be freed from the risk of serious habitat alteration. The eradication of Sagina on Gough Island by a project run from Tristan da Cunha with Tristan Islanders actively involved at both managerial and operational levels will help foster the feeling of pride in their conservation efforts that already exists. Internationally, arguably the world's most important seabird island and one of the world's most pristine southern cool temperate oceanic islands will be protected for its intrinsic value and as a site where important biological and conservation-oriented research has been and will continue to be conducted. Such research is to the benefit of global conservation knowledge and to the spread of best conservation management practices. Complete and final eradication of Sagina will help preserve Gough Island in a natural state as is possible. Continued monitoring on an annual basis of the area(s)of known occurrence of Sagina as well as elsewhere on the island will be necessary. Removal by chemical and physical means of any remaining and newly emerged plants found will need to continue for a number of years. It is envisaged that these activities can be undertaken by the combined efforts of South African volunteers based at the meteorological station on a month-to-month basis, and by intensive inspections by the Tristan-appointed Environmental Officer during the annual relief visits to the island by the South African supply ship. Outputs The project will deliver a Gough Island Nature Reserve free of an alien plant known to be strongly invasive at similar oceanic island sites. Measurement of achievement will be by continued monitoring and removals until no new plants have been found for a period of two years. Legacy Tristan da Cunha has a tight-knit community. Environmental awareness will be heightened by informal communication among friends and family members, including children, from Islanders after they return from field seasons at Gough Island.More formally, the opportunity will exist for Tristan school children to become involved by receiving illustrated talks from field workers, and by undertaking school projects on the Sagina eradication, etc. An important part of such activities would be an increase in the knowledge of Gough Island and its many globally important aspects (endemic and threatened species, magnificent landscape features, etc.) gained by school children in an exciting way about an island that is otherwise remote and is seldom visited by Tristan Islanders themselves. Post-project monitoring will continue as describe above until no new Sagina plants have been found on Gough Island for a minimum period of two years.Post-project monitoring will be undertaken by TDNR staff and GINRAC members and by the annually appointed Environmental Officer who accompanies the South African relief voyage. Close collaboration between TDNR, GINRAC and experts (especially Dr Gremmen) by way of regular spoken and written communications will ensure that TDNR as the lead local stakeholder gains a full knowledge of and experience with all managerial and operational procedures.Experts in addition to Dr Gremmen may be invited to accompany project and/or post-project relief voyages if considered warranted (e.g. if a new infestation is discovered away from the meteorological base, or to test any newly available or proposed eradication measures). Objectives The alien plant, Procumbent Pearlwort Sagina procumbens, was first observed at Gough Island in the immediate vicinity of the South African meteorological station in September 1998. Since discovery, volunteer efforts by South African meteorologists, acting under the guidance of the Gough Island Nature Reserve Advisory Committee (GINRAC) and an expert botanist in oceanic islands and invasive species (Dr Niek Gremmen) and utilizing both chemical and physical methods, have restricted the plant's spread to a small (<1-ha) area. The project aims to eradicate Sagina at Gough Island by way of a dedicated two-person team with the necessary skills and experience who will be stationed at the island for extended periods of time over a two-year period. Contributions to Local Strategies and Action Plans The Gough Island Nature Reserve has a management plan adopted in 1994, which is currently under revision. The management plan requires the eradication of localized introductions of alien plants by regular weeding and ensuring there is no opportunity for dispersal. Contributions to Multilateral Environmental Agreements Gough Island, along with Inaccessible Island in the Tristan da Cunha group, is a proclaimed Natural Site under the World Heritage Convention. The original inscription was agreed to in 1995, and extended in 2004 with new boundaries that include Inaccessible Island. Wider Significance Sagina occurs on the main island of Tristan da Cunha, but not, as far as it is known, on the other islands in the group. Experience learnt on Gough will help TDNR develop and retain the skills needed to identify alien plants in the Tristan-Gough Islands and plan for and effect their successful control and/or eradication. On a wider scale the experience learnt will be of value on an international scale as eradicating efforts for alien plants are planned and attempted on other oceanic islands.The project will support the wider goal of working towards preserving the world's uninhabited and little-altered oceanic islands for posterity, and for their own intrinsic worth. Other Information Funded by FCO/DFID Overseas Territories Environment Programme, 2005 Project No. TDC 201
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