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The main outcome of the project was the control or significant reduction of chromolaena in most provinces of PNG. Areas that were once monostands of chromolaena have been converted back into subsistence farms, and plantations in which chromolaena was the main understorey species are now clear of the weed. This outcome was the result of the primary outputs of the project: (a) knowledge of the extent of the chromolaena problem and its impact of the livelihoods of smallholders, (b) an understanding of effective biocontrol agents and (c) significant capacity built in biocontrol of weeds.

Cane toads introduced to Queensland in 1935, are major environmental pests in Western Australia, having arrived here in February 2009. The Liberal National Government released a 10-year Cane Toad Strategy for Western Australia in 2009. Over the first five years of the strategy, much has been achieved and the government has invested more than $7.8 million in on –ground activities and research to help control the spread of can toads. With a range of stakeholders, including community groups, universities, the Australian Government, local shires, Indigenous groups and others, the State of Government has implemented many new can toad management programs including a field-based cane toad surveillance and response team, strengthened quarantine measures, a free-call hotline to report cane toad sightings and cane toad drop off points. Major biological survey work has provided benchmark information on important island wildlife populations that need priority protection from cane toad. Biological controls are also being researched for the survival of native wildlife species in the short and medium terms and management of cane toads in the longer term. Educating the community has prevented new populations from establishing in Perth and elsewhere. Detector dog specially trained to sniff out cane toads is a proactive measure to stem the spread of this noxious pest. This is a review and update on the original 10 year strategy to review and update the strategy to reflect progress in implementation, the current status of cane toads in WA and results of ongoing research, and to refocus its aims and objectives. Cost effective activities and an integrated approach with other initiatives across WA, such as the $81.5 million Kimberley Science and Conservation Strategy, are required. The revised Cane Toad Strategy for Western Australia 2014-2019 will ensure the available information is used to inform Wa’s continued management of cane toads.

The last two decades have seen an upsurge in research into the potential synergies between invasive species and climate change, with evidence emerging of increased invader success under climate change. All stages along the naturalization-invasion continuum are likely to be affected, from the introduction and establishment of alien species to their spread and transition to serious invaders. A key question is whether alien plants will have a relative advantage under climate change conditions. So far, evidence for differential responses of alien invasive and native species to climate change drivers (elevated CO2) and outcomes (increasing temperature, changing rainfall patterns, changes in disturbance regimes) is mixed. Although alien invasive plants appear to be more responsive to elevated CO2 than many native species, plant response to elevated CO2 and other climate change components is dependent on environmental conditions and resource availability. Similarly, correlative modelling of species-climate relationships has not revealed clear evidence that invasive plants are likely to be able to increase the extent of suitable habitat under future climates any more than their native counterparts. We suggest that the most important driver of a shift to alien-dominated vegetation under climate change will be the superior capacity of alien invasive plants to take advantage of colonisation opportunities arising from climate change, such as extreme climatic events, changes in disturbance regimes, and widespread reduction in vegetation resilience as range margin populations decline. There are substantial challenges ahead for managing invasive plants under future climates. Weed risk assessment and management approaches must incorporate consideration of future climatic conditions. Most importantly, we will need a shift in management approaches away from a focus on the control of undesirable alien plant species to building resilience of resident vegetation assemblages, in association with targeted monitoring and early eradication of alien plant species.

In September 2003, Hurricane Isabel caused unexpectedly high levels of wind damage to an 80-to 100-year-old forest in the Piedmont of Maryland. The storm had decreased in intensity from landfall by the time it reached the study site—sustained winds were moderate and maximum gusts recorded in the area were only 62.7 mph (28.1 m?s-1). Midsized gaps (up to 1 ha) were created in forest that historically had only small or single-tree gaps. Isabel created the opportunity to determine whether natural disturbance facilitates the spread of exotic invasive plant species. Exotic invasive species populations were sampled in 400 5 x 5 m quadrats in a heavily damaged 1-ha, long-term forest study plot and in 160 5 x 5 m quadrats in 0.4 ha of a nearby, less-damaged forest between mid-October and mid-December 2003. Light levels (quantum flux density of photosynthetically active radiation) in the heavily disturbed Permanent Plot and the Less Damaged control plot were surveyed in October 2003 and 2004. The fall 2004 resurvey for exotic plants has also been completed. Based on a random sample of the fall 2004 exotics data, exotic invasive plant species responded strongly to the increased light levels in patches of forest damaged by Isabel. Collectively, the mean increase in percentage cover of exotic plants was 47.8% in high-light canopy gaps versus only 4.8 % in low-light non-gaps and 4.2% in the less-damaged forest. Several individual exotic species—Polygonum perfoliatum, Polygonum positive responses to higher light levels. The shadeloving caespitosum, and Lonicera japonica had significant biennial, Alliaria petiolata, changed significantly in the opposite direction, decreasing in the high-light areas and increasing in the lowlight areas. The authors are also investigating the interaction of exotic plants with native plants, forest regeneration, and white-tailed deer (Odocoileus virginianus) in damaged areas. Study areas and exclosures for these projects were set up in 2004 and will be resurveyed beginning in 2005.

Le Centre assure l’élaboration de méthodes, le développement de formations, la capitalisation des connaissances et la diffusion de savoir-faire et de bonnes pratiques. Il consacre ainsi son activité à toutes les EEE de faune et de flore, en milieux terrestres, marins et d’eau douce, en métropole comme en outre-mer.

Website for invasive species for France

especes exotiques envahissantes.france uicn guide

Des invasions biologiques aux conséquences multiples: Les espèces exotiques envahissantes (EEE dans la suite de l‘ouvrage) constituent l’une des principales pressions sur la biodiversité à l’échelle mondiale, au même titre que la destruction des habitats naturels, la surexploitation des ressources, les pollutions ou le changement climatique. Les espèces introduites, lorsqu’elles se révèlent envahis¬santes, provoquent des impacts multiples, directs ou indi¬rects, affectant les espèces indigènes, les habitats naturels et les services rendus par les écosystèmes, mais égale¬ment les activités économiques et la santé humaine. Partout dans le monde, à des échelles géographiques et des intensités très variables, les EEE provoquent des altérations du fonctionnement des écosystèmes et causent la régres¬sion d’espèces indigènes. Selon les dernières estimations de la Liste rouge des espèces menacées de l’UICN, elles constituent une menace pour près d’un tiers des espèces terrestres menacées de disparition et sont impliquées dans la moitié des extinctions connues (UICN France, 2015). Sur le plan économique, les conséquences négatives des invasions biologiques peuvent être très importantes (Ket¬tunen et al., 2009). Les impacts qui génèrent des coûts économiques pour divers acteurs ou la société d’une manière générale sont multiples : dépréciation des rende¬ments agricoles, coûts sanitaires, coûts de régulation des invasions de ces espèces sur le terrain, coûts de restaura¬tion des milieux naturels envahis et, de manière plus diffi¬cilement quantifiable, les impacts sur les services rendus par les écosystèmes. Sur le plan sanitaire, de nombreuses espèces introduites constituent de plus une menace pour la faune et la flore ou pour la santé humaine. Elles peuvent être allergènes, pa¬thogènes ou toxiques, ou encore constituer des réservoirs ou des vecteurs de micro-organismes et virus pathogènes.

Retrouvez le site de l’initiative largement mis à jour et notamment une description des enjeux et de l’initiative, les actualités, bases de données et ressources. Vous y trouverez également une page et la base de données spécifiques à la Nouvelle-Calédonie.

Suite à la soutenance de thèse effectuée en juillet 2018 à l’Université de Massey, le manuscrit de Martin Thibault, intitulé « Le bulbul à ventre rouge (Pycnonotus cafer): dynamique d’invasion et impacts écologiques d’un oiseau introduit en Nouvelle Calédonie. Invasive alien species are a major cause of biodiversity loss globally, especially on islands where high species richness and levels of endemism accentuate their impacts. Various international institutions have constructed lists of the most harmful invasive species to help environment managers at both global and local scales to prioritize their efforts. The red-vented bulbul (Pycnonotus cafer) is a passerine bird species considered among the three worst invasive birds on the planet. This species is currently spreading over the tropical archipelago of New Caledonia, one of the 36 world biodiversity hotspots. This dissertation presents the findings of a PhD study conducted in New Caledonia with two objectives: 1) to describe this introduced population, and 2) to evaluate the threats from its dispersal using both existing knowledge and new in-situ and ex-situ data and a variety of analysis techniques. From the literature, I identified three key impacts explaining the species’ status: i) damage to agricultural crops, ii) noxious seed dispersal, and iii) competition with other avifauna. I estimated the local population size (approx. 140,000 individuals), its habitat use (inhabited areas), its density along an urbanization gradient (30-120 ind/km2), and I produced lists of consumed plant and animal species and identified a colour preference in the foraging strategy of the red-vented bulbul. Exploration of each impact category revealed i) substantial losses on fruit production (18% of tomato production), ii) impact on the abundance of nine native bird species that may be driving a spatial reassembly of the community, and iii) a short distance dispersal (77-92 m) that could promote the dispersal of introduced plant species at the expense of endemic species. Finally, through modelling, I estimated the climatic niche of the species at a global scale and identified that most island territories as suitable for the establishment of this invasive bird species. Regardless of whether the red-vented bulbul deserves its status as “world worst” species, quantitative impact assessments in its alien range such as the studies presented here are needed to prevent the dispersal and harmful impacts of this species on human activities and sensitive ecosystems. Implications for management are discussed.