Understanding and Addressing the Impact of Invasive Non-Native Species in the UK Overseas

Understanding and addressing the impact of invasive non-native species in the UK Overseas Territories in the South Atlantic: A review of the potential for biocontrol

DEFRA ref: CR 0492CABI ref: TR10086

Preliminary list of references

Norbert Maczey, Rob Tanner and Richard Shaw

March 2012

Contents

Norbert Maczey

Senior Ecologist/Entomologist

CABI

Bakeham Lane

Egham, Surrey

TW20 9TY

UK

T: +44 (0) 1491 829029

E:

Project introduction

Recent reviews of invasive non-native species (INNS) onthe South Atlantic UKOTs, revealed that there is a considerable on-going threat by these species to the endemic biodiversity on these islands. Management plans and capacity building efforts to combat invasive plants have already been developed, or are in the process of being developed, by various conservation bodies and other research institutions. However, to-date, there are few plans to include classical biological control in these new schemes despite this management practise having a long history of successful use on islands in the past.We understand that many species including rare, endangered and/or iconic species are negatively impacted upon by introduced invasive plants or invertebrate species and that the reduction of their impact through biological control could bring tangible benefits to biodiversity in these fragile habitats. At present there is little known about the potential of this tool in South Atlantic UKOTs and therefore this feasibility study focuses on the future potential usage of this method.

A major component of this study is a desk-based review assessing the impact of non-native plant and invertebrate species in the South Atlantic UKOTs.We rank the need and suitability for biological control of individual invasive species, from high to low, using a recently-developed weed biocontrol prioritisation tool, developed initially for Australia, but already proving to be very useful on the islands in the South Pacific.Priority species are selected on the basis of population dynamics, reported impact on biodiversity, impact on livelihoods, costs for on-going control measures other than biological control and others.

In addition, two detailed case studies will evaluate the potential of implementing a biological control programme against priority species for the Falklands and South Georgia more closely. These detailed assessments will combine all current information about the target pest species including information on their native range, areas of introduction and recorded natural enemies in their areas of origin. Ranked in order of priority, and associated costs of available control options, we will include a catalogue of recommended strategies for each priority target species aimed to halt the biodiversity loss through invasive plant and invertebrate species more effectively.

References

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BAPs regarding IAS on SAUKOT

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BC of IAS on SAUKOT

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