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The aim of this toolkit is to provide a clear, user-friendly guide to the application of economic approaches and tools to invasive species. It addresses the issues associated with identifying the factors which cause the spread of invasives, incorporating consideration of invasive species into economic planning and policy-making, and identifying economic tools and measures to support on-the-ground management actions designed to address biological invasions. This toolkit has been produced for use in training courses to be held in Africa. It is targeted primarily at economists working in research and planning – in universities, research institutions, government agencies and non-governmental organisations. However, it is intended that the toolkit will also provide guidance on economics tools and approaches to scientists who are working on invasive species management.

Agriculture and food production offer stable livelihood options to rural communities throughout Asia and the Pacific region. Even as the effects of globalization spread in the region, farm production – most often at the smallholder level – continues to be a family enterprise. A fair share of farmers in the region engages in subsistence farming and poverty is a common occurrence among them. Farm enterprises are mostly managed by family members and family labour is a critical asset and often the only reliable investment. As rural women and men toil to preserve their heritage and broaden their economic choices, their endeavours are made more difficult by a lack of resources and market fluctuations. Asian and Pacific farmers, both men and women, are guardians of biodiversity, household food security and providers of food to urban communities. In these small farm enterprises distinct gender roles and gender differentiated access to technology and resources are evident. This disparity is compounded by the neglect of investment in rural social infrastructures such as education, health care and communications. In such resource poor rural environments, the struggle by rural women for access to resources and services is inevitable. In many Asian and Pacific countries, substantial gender equality gains have been made in urban areas in education, health and employment. Yet rural women lag behind. Moreover, rural women’s work is multifaceted and demanding both as family workers and agricultural labourers. Social and economic indicators often do not do justice to their contributions. Development innovations such as microcredit and self-help groups promote rural women’s economic development, but emerging evidence suggests that gender equality in rural communities is far from an everyday reality. Persisting social biases and traditional perceptions and assumptions regarding women’s responsibilities and their capacities continue to hamper women’s progress. This publication presents an overview of both the substantial contribution made by rural women to the economies in the region and the persisting barriers to their advancement. The framework of analysis, data and information reviewed together illustrate the complexity of rural women’s work in the region and offer a broad perspective on women’s economic and social contribution as well as on the barriers they encounter in accessing resources.

Questions: Do past disturbance, soil nutrients, or species diversity predict the invasion success of the alien tree Pittosporum undulatum in an island montane rain forest? What are the consequences of its invasion for forest composition and species diversity? Location: Blue Mountains, Jamaica. Methods: Censuses of trees ? 3 cm DBH in permanent plots in four sites within ca. 7 ha; 1974–2004 (intensive sites) and in 16 plots within 250 ha; 1990–2004 (extensive plots). Results: Pittosporum was unrecorded in the intensive sites before a severe hurricane in 1988: by 2004 all four sites were invaded. Pittosporum had invaded 25% of the extensive plots in 1990 and 69% in 2004, where its basal area increased from 0.5 ± 0.4 (SEM) m2.ha?1 in 1990 to 2.8 ± 1.3 m2.ha?1 in 2004. It had zero stem mortality and diameter growth rate exceeded that of native species fourfold. Pittosporum's basal area in the extensive plots in 2004 was positively related to the stand basal area damaged in the 1988 hurricane and negatively related to soil N concentrations. Pittosporum invasion was unrelated to stand-level tree species diversity in the extensive plots but as its basal area increased over time the basal area of native species and stand-level diversity declined. Conclusions: There are no obvious functional attributes of Pittosporum unrepresented in the native tree flora although it has high photosynthetic efficiency compared with native trees. More widespread invasion of these forests by Pittosporum seems inevitable since hurricanes, which accelerated the invasion, affect these forests frequently.

Disturbances are a primary facilitator of the growth and spread of invasive species. However, the effects of large-scale disturbances, such as hurricanes and tropical storms, on the broad geographic patterns of invasive species growth and spread have not been investigated. We used historical aerial imagery to determine the growth rate of invasive Phragmites australis patches in wetlands along the Atlantic and Gulf Coasts of the United States. These were relatively undisturbed wetlands where P. australis had room for unrestricted growth. Over the past several decades, invasive P. australis stands expanded in size by 6–35% per year. Based on tropical storm and hurricane activity over that same time period, we found that the frequency of hurricane-force winds explained 81% of the variation in P. australis growth over this broad geographic range. The expansion of P. australis stands was strongly and positively correlated with hurricane frequency. In light of the many climatic models that predict an increase in the frequency and intensity of hurricanes over the next century, these results suggest a strong link between climate change and species invasion and a challenging future ahead for the management of invasive species.

This paper examines how optimal prevention and control policies depend on the economic and biological characteristics of a randomly introduced biological invasion where the objective is to minimise the expected social costs from prevention, control, and invasion damages. The results characterise how optimal prevention and control policies vary with the initial invasion size, the invasion growth rate, and the probability distribution of introductions. The paper also examines the conditions under which the optimal policy relies solely on either prevention or control, the conditions under which it is optimal to completely prevent new introductions, and the conditions under which eradication of established invasions is optimal.

The restoration of the Islands of Nuutele and Nuulua is a priority of the Government of Samoa and the communities of Aleipata District. Planning is well advanced on a key element of this, the eradication of Pacific Rats (Rattus exulans) by aerial spreading of toxic baits in mid-2006. The Friendly Ground Dove has been identified as a non-target species that may be at risk of taking the baits and one for which the Nuutele and Nuulua populations are significant. Several approaches for safeguarding these have been discussed and this expedition was designed to test the feasibility of the preferred approach, namely the capture and holding of birds in a safe situation on Nuutele during the aerial operation and their release once the baits are non-toxic.

In 1989, the kakerori (Pomarea dimidiata) was one of the 10 rarest bird species in the world, with a declining population of just 29 birds. During each breeding season since then, rats have been poisoned within the 155 ha of forested hill country they occupy in the Takitumu Conservation Area in southeastern Rarotonga. As a result, the kakerori population has rebounded, with a minimum of 292 birds found on Rarotonga in August 2003. In 2001/02, the emphasis of management shifted from the .recovery. of kakerori to a programme aimed at .sustaining. the population at 250.300 individuals. The major changes were an experimental reduction in rat poisoning effort to a level where recruitment of kakerori balances annual mortality, and a series of transfers to establish an insurance population on the island of Atiu. In 2003/04, all bait stations were filled fortnightly, rather than the previous mix of weekly and fortnightly refills. This reduced labour costs by 30% to 32 person days, and used a total of 39 kg of Talon® (active ingredient brodifacoum), which was only 13% of the maximum annual poison use over the same area during the .recovery. phase of the programme. Breeding success was high (0.91 fledglings/ breeding territory), even in the unpoisoned areas, and a record total of 80 fledglings was detected. The fortnightly poisoning regime offers promise as an effective, cheaper and less toxin-intensive method than that used previously, and so we recommend maintaining this regime in 2004/05, so that the longerterm effects can be assessed. A third and final batch of 10 young kakerori was transferred to Atiu Island in August 2003. This .insurance. population is becoming well established; the five breeding pairs monitored in 2003/04 each raised two fledglings, and a minimum of 15 birds was found in May.June 2004 in the small part of the island that was searched.

SPREP's direction in the Islands Ecosystems Programme reflects a fundamental commitment to sustaining the livelihoods of island peoples today and tomorrow by supporting ecosystem management and species conservation. The Programme focuses on developing the capacities of the peoples of the Pacific islands to equip them to sustainable manage and conserve the terrestrial, coastal and marine ecosystems of their islands. The programme also focuses efforts to protect priority threatened species, and to protect Pacific island countries and terrttories (PICTs) from invasive alien species and living modified organisms (LMOs). In summary, SPREP's core business under this programme is to address the issues of ecosystem conservation, the sustainable management of natural resources and the protection of priority threatened species from the threats of human-induced impacts, invasive species and living modified organisms. These issues require action at the community, national,regional and international levels.

SPREP’s direction in the Islands Ecosystems Programme reflects a fundamental commitment to sustaining the livelihoods of Island peoples today and tomorrow by supporting ecosystem management and species conservation. The Programme focuses on developing the capacities of the peoples of the islands to equip them to sustainably manage and conserve the terrestrial, coastal and marine ecosystems of their islands. The Programme also focuses efforts to protect priority threatened species, and to protect Pacific island countries and territories (PICTs) from invasive alien species and living modified organisms (LMOs). SPREP’s core business under this programme is to address the issues of ecosystem conservation, the sustainable management of natural resources and the protection of priority threatened species from the threats of human-induced impacts, invasive species and living modified organisms. These issues require action at the community, national, regional and international levels.