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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.

Quarantine (Biosecurity) Act 2005

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.

Invasive species are plants or animals living where they don’t belong and causing harm. Also known as introduced, alien or pest species, they are species that have been brought into a new environment and whose introduction can : Threaten many native and endemic species with extinction by eating them or competing for food, light, water or shelter Damage ecosystems so that they are less able to provide essential services such as clean water, erosion protection, insect control etc Harm humans and animals from bites, stings or disease Reduce the tourism attractiveness of an area Impact on the species that Pacific Islanders rely on for their livelihoods

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.

The islands of Nu'utele and Nu'ulua have been identified as highly significant sites for conservation in Samoa. They hold large populations of species currently found nowhere else in the country' including threatened land-birds, seabirds and nesting turtles. They also are the only offshore islands large enough and far enough offshore to be considered as refuges for several of the nation's species threatened on the larger islands by introduced mammalian pests. Such refuges have assumed greater importance as recent severe cyclones (Ofa - 1990, Val - 1991 & Heta - 2004) have reduced bird and bat numbers.

For one of the species potentially at some risk of poisoning under the proposed rat eradication regime, the Friendly Ground Dove, Nuutele and Nuulua hold populations that are nationally significant. The complete loss of these populations would threaten the survival of the taxon in Samoa. Some authors consider the Samoan doves to be a separate race (Gallicolumba s. stairi) from those in Fiji and Tonga (Watling, 2001). Outside Samoa, the race is only found on the small island of Ofu, American Samoa where it is threatened. So the loss of Nu’utele and Nu'ulua birds could threaten the race with extinction.