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This report is targeted at policy-makers, particularly those responsible for developing climate mitigation and adaption strategies that address issues like conservation, ecosystem services, agriculture and sustainable livelihoods. It focuses on the primary linkages between invasive species and climate change, as well as the secondary and tertiary interactions of their corresponding impacts. Finally, the enclosed recommendations are intended to provide guidance on the best ways to integrate invasive species prevention and management into the consideration of climate change responses across a range of sectors. Building on a review of existing scientific and conservation literature (which is frequently centered on well-studied invasive species in developed countries), our research has reaffirmed that there are significant gaps and questions about the intersection of these two major drivers of change. The case studies included below highlight key relationships and questions related to invasive species, climate change and the role of ecosystem-based adaptation. The three key messages that can be distilled from this report are: 1. Climate change will have direct and second order impacts that facilitate the introduction, establishment and/or spread of invasive species. 2.Invasive species can increase the vulnerability of ecosystems to other climate-related stressors and also reduce their potential to sequester greenhouse gasses. 3.Using an ecosystem-based adaptation approach, these pressures on ecosystems and their ability to provide important services can be offset by preventing the introduction of new invasive species and by eradicating or controlling those damaging species already present.

Pacific Invasives Initiative: strategic plan 2010-2015

4 page Fact sheet provides general information to background history, description of Cane Toad in different life stages, why they are invasive pest, and control actvities

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.

The effects of alien invasive species on biodiversity have been described as “immense, insidious and usually irreversible” (IUCN 2000). There is no doubt that invasive species can cause severe economic and ecological damage (Mack et al. 2000). They may soon surpass habitat loss as the main cause of ecological disintegration globally (Vitousek et al. 1997, Chapin et al. 2000) and are probably already the main cause of extinctions in island ecosystems. The breaching of biogeographic boundaries by the widespread, recent human transport of species has caused rapid and radical change in biological communities, including multiple extinctions. To minimise further extinctions and other ecological changes, the most important priority is to reduce the risks of new invasions. After prevention, the next priority is to eradicate existing invasive species, where this is possible. These aims are embodied in the United Nations Convention on Biological Diversity, which states that parties to this convention should “ prevent the introduction of, control or eradicate, those alien species which threaten ecosystems, habitats or species”.

Eradication of Island invasives: practical actions and result achieved at the University of Auckland, 19-23 February, 2001

Worst invasive species list in the world, a selection from the global invasive species database

Native forest species exhibit a well-known range of ecological roles with respect to natural disturbance regimes, from pioneer phase to mature phase, and they regenerate from a range of sources, including dormant seeds, seed rain, pre-established juveniles, and resprouts from damaged adults. In contrast, the ecological roles of invasive, non-indigenous species in forest communities after natural disturbances are not well understood. Some previous studies of invasive species have emphasized their weedy nature and their ability to colonize anthropogenic disturbances. Tropical hardwood hammock forest in southern Florida experience frequent disturbance by hurricanes. Our studies of forest regneration during two years following a recent severe hurricane suggest that invasive non-indigenous forest species exhibit the same range of ecological roles as native forest regeneration during two years following a recent severe hurricane suggest that invasive non-indigenous forest species exhibit the same range of ecological roles as native forest species and compete with native species for particular kinds of regeneration opportunities. To study ecological roles of non-indegenous species in regenerating forests after Hurricane Andrew, we set up four large study areas at each of three study sites that had differing amounts of hurricane-caused canopy disturbance. There were two pairs of 30 X 60 m research plots per site, and in each pair there was one control plot and one restoration plot; restoration areas were subject to an aggressive management program, focused on reducing non-indigenous vine cover. Within these study areas we subsampled vegetation in small study plots that were regularly spaced, and conducted vegetation censuses in April (the end of the dry season) and October (the end of the rainy season) for 2 yr, beginning in April 1993. We found that the source of regeneration for forest species was dependent upon the amount of canopy disturbance, the time since disturbance, and the autecology of the constituent species. Overall, 28% of the 90 species were non-indigenous: 34% of the vines (N=32) and 24% of other life-forms (N=58). Non-indigenous vines seemed to have a special role; not only could they compete with native vines, but they could also negatively affect the regeneration of other natives from a diverse array of sources including pre-established juveniles and resprouts from damaged adults. Both native and non-indigenous vine cover in unmanipulated study areas increased following the hurricane. Non-indigenous vine species had higher cover than native vine species, and many species formed dense "blankets." Non-indigenous species in general (not just vines) did not differ significantly from native species in seed mass, nor were they restricted to the pioneer type of life history. Many non-indigneous species had invaded forests prior to hurricane disturbance and had their own banks of pre-established juveniles; others recruited from dormant seeds, and seed rain, and/or respouts from pre-established adults. Based on information on source of regeneration and impact on native species, we propose a classification scheme for functional roles of non-indigenous invasive species in forests. To investigate whether non-indigenous taxa had roles in other geographic regions similar to those they had in Florida, we reviewed literature for 50 taxa belonging to genera that have species known to be invasive in southern Florida. We found that these taxa were invsive or had cogeners that were invsive in other geographic regions (Western Australis, the Mariana Islands, Hawaii, the rMascarene Islands, and South Africa). We propose that taxa predominantly retain their invasive, functional-role type across regions. Thus, studies of ecological roles of invasive species with respect to natural disturbance regimes in one region may help us predict invasive roles in other regions.