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Barré, N.

Brescia, F.

Demaret, L.

Fogliani, B.

Jourdan, H.

Lannuzel, G.

Masse, F.

Potter, M.A.

Pujapujane, A.

Robert, N.

Thibault, M.

Vidal, E.

New Caledonia is a tropical archipelago of the South Pacific Ocean, and is one of the 36 world biodiversity hotspots. However, its unique biodiversity is increasingly threatened by habitat fragmentation and introductions of invasive alien species. Among these invaders, the red-vented bulbul (Pycnonotus cafer) is currently expanding towards the north of the main island. This passerine features in the IUCN-ISSG list of the 100 worst invasive species of the world because of impacts caused by its diet. Thirty-five years after its introduction, we present an overview of data from recent studies conducted in New Caledonia that describe the local status of the red-vented bulbul, its range expansion, and potential impacts on both the local biodiversity and agriculture. Biannual monitoring of the distribution coupled with surveillance at the edges of native forests highlighted a tight association of the bulbul with man-modified habitats. Using a distance sampling method, we estimated that bulbul densities within the distribution core varied from a peak of 200 individuals/km2 in the main city of Nouméa, where the species has been introduced, to 30 individuals/km2 in rural habitats located 50 km away from Nouméa. We conducted a diet analysis on 40 bulbul corpses and found that 82% and 55% of individuals had consumed plant and animal items, respectively. We identified plant and insect species that may be of concern in the contexts of seed dispersal and predation by the red-vented bulbul. Finally, a food colour selection experiment and an open field test showed that the red-vented bulbul had a significant preference for red and sweet fruits. We estimated the economic loss caused by bulbuls to a tomato grower and discuss the result with respect to the development of an adapted management strategy, to prevent further impacts of the red-vented bulbul on the biodiversity and agriculture in the tropical island hotspot of New Caledonia.

Population assessment of a novel island invasive: tegu (Salvator merianae) of Fernando de Noronha

Abrahão, C.R.

Dias, R.A.

Ferreira, F.

Russell, J.C.

Silva, J.C.R.

Fernando de Noronha is an oceanic archipelago in the Atlantic Ocean, 345 km off shore from the Brazilian coast. It comprises 21 islands and islets, of which the main island (FN) is 17 km2 with a rapidly growing tourism industry in the last decades. Despite being a protected area and bearing Ramsar and UNESCO World Heritage site status, it is threatened by multiple terrestrial invasive species since its colonisation in the early 16th century. Invasive species and the increasing tourism contributes to a list of at least 15 endangered or critically endangered species according to IUCN criteria. The black and white tegu (Salvator merianae) is the largest lizard in South America, occurring in most of the Brazilian territory and reaching up to 8 kg and 1.6 m from head to tail. As an omnivorous and opportunistic lizard, it feeds on a variety of available items, including smaller vertebrates and eggs. The introduction of the tegu to FN as well as its immediate impact on local fauna were not recorded; however, its ongoing impact is expected to be high. We captured and marked 103 tegu in FN during the months of February and November of 2015 and 2016. We also counted animals by line-transect census in a sparsely inhabited and an uninhabited area of FN. Body size affected the capture probabilities, while season and sex had little or no effect. Densities estimated by capture-recapture in the sparsely inhabited area varied from 2.29 to 8.28 animals/ha according to sampling season. Line transect census in the same area revealed a density of 3.98 (±1.1) animals/ha and in the uninhabited area 13.83 (±3.9) animals/ha. Home range was 10.54 ha, ranging from 7.36 to 15.33 hectares. Tegu activity decreased in the months of July and August of 2015. Results from this study can assist conservation managers and decision makers to implement a science-based tegu management programme in the future.

Five eradications, three species, three islands: overview, insights and recommendations from invasive bird eradications in the Seychelles

Agricole, J.

Angell, G.

Banville, P.

Bunbury, N.

Constance A.

Fleischer-Dogley, F.

Friedlander J.

Haverson, P.

Leite, L.

Mahoune, T.

Melton-Durup, E.

Moumou, J.

Page, N.

Raines, K.

van de Crommenacker, J.

Management and eradication techniques for invasive alien birds remain in their infancy compared to invasive mammal control methods, and there are still relatively few examples of successful avian eradications. Since 2011, five separate eradication programmes for invasive birds have been conducted on three islands by the Seychelles Islands Foundation (SIF). Target species were prioritised according to their threat level to the native biodiversity of the UNESCO World Heritage Sites of the Seychelles, Aldabra Atoll and Vallée de Mai, which SIF is responsible for managing and protecting. Red-whiskered bulbuls (Pycnonotus jocosus) and Madagascar fodies (Foudia madagascariensis) occurred on Assumption, the closest island to Aldabra, which, at the time, had no known introduced bird species. The growing population of ring-necked parakeets (Psittacula krameri) on Mahé posed a threat to endemic Seychelles black parrots (Coracopsis barklyi) on Praslin where the Vallée de Mai forms their core breeding habitat. In 2012, red-whiskered bulbuls and Madagascar fodies were detected on Aldabra, so an additional eradication was started. All eradications used a combination of mist-netting and shooting. The intensive part of each eradication lasted three years or less. On Assumption, 5,279 red-whiskered bulbuls and 3,291 Madagascar fodies were culled; on Mahé, 545 parakeets were culled; and on Aldabra 262 Madagascar fodies and one red-whiskered bulbul were culled. Each programme underwent 12 years of follow-up monitoring before eradication was confi rmed, and four of the fi ve eradications have been successful so far. None of these species had previously been eradicated in large numbers from other islands so the successes substantially advance this fi eld of invasive species management. The challenges and insights of these eradications also provide unique learning opportunities for other invasive avian eradications.

House sparrow eradication attempt on Robinson Crusoe Island, Juan Fernández Archipelago, Chile

Bonham, J.

Campbell, K.

Hagen, E.

House sparrows (Passer domesticus) compete with native bird species, consume crops, and are vectors for diseases in areas where they have been introduced. Sparrow eradication attempts aimed at eliminating these negative effects highlight the importance of deploying multiple alternative methods to remove individuals while maintaining the remaining population naïve to techniques. House sparrow eradication was attempted from Robinson Crusoe Island, Chile, in the austral winter of 2012 using an experimental approach sequencing passive multi-catch traps, passive single-catch traps, and then active multi-catch methods, and finally active single-catch methods. In parallel, multiple detection methods were employed and local stakeholders were engaged. The majority of removals were via passive trapping, and individuals were successfully targeted with active methods (mist nets and shooting). Automated acoustic recording, point counts and camera traps declined in power to detect individual sparrows as the population size decreased; however, we continued to detect sparrows at all population densities using visual observations, underscoring the importance of local residents participation in monitoring. Four surviving sparrows were known to persist at the conclusion of eff orts in 2012. Given the lack of formal biosecurity measures within the Juan Fernández archipelago, reinvasion is possible. A local network of citizen observers is the best tool available to detect house sparrows at low density, however ongoing, dedicated eradication funding does not exist. Opportunistic removals via shooting have been possible from 20132016, but elusive individual sparrows were seen during a small number of days each year suggesting remnant group(s) exist in yet unknown forest locations.

Pacific Regional Invasive Management Support Services (PRISMSS) Invasive species programme management course

BRB

Factsheet for the Invasive species programme management course

Pacific Regional Invasive Species Management Support Service (PRISMSS)

SPREP Publications, Biodiversity Conservation, BRB

The PRISMSS is a regional mechanism, which facilitates the scaling up of invasive species management in the Pacific. It provides management support for on the groud invasive species actions

Using the mitigation hierarchy to manage impacts on biodiversity in Pacific island countries and territories = Renforcer la hiérarchie datténuation1dans les Etats et Territoires Insulaires Océaniens.

BRB

The mitigation hierarchy (MH) is a step-by-step tool used to limit the negative impacts of development projects. It can be used for many disciplines; this guidance note focuses on its use to manage risks and impacts to biodiversity. Very similar approaches can be used for ecosystem services and even social impacts.

Rat and lagomorph eradication on two large islands of central Mediterranean: differences in island morphology and consequences on methods, problems and targets

Baccetti, N.

Capizzi, D.

Cencetti, T.

De Pietro, F.

Giannini, F.

Gotti, C.

Puppo, F.

Quilghini, E.

Raganella Pelliccion, E.

Sammuri, G.

Sposimo, P.

Trocchi, V.

Vagniluca, S.

Zanichelli, F.

Montecristo and Pianosa islands, although approximately equal in surface area (c. 1,000 ha), di?er greatly in substrate, human presence, vegetation and altitude (650 m vs. 30 m asl, respectively). The former island hosts one of the largest yelkouan shearwater (Pu?nus yelkouan) populations in Italy, the latter a depleted remnant of once numerous Scopolis shearwaters (Calonectris diomedea). Two consecutive EU-funded LIFE projects have been designed to protect these seabird populations. On Montecristo, rough and inaccessible, aerial delivery of toxic baits in January-February 2012 eradicated black rats (Rattus rattus) and feral rabbits (Oryctolagus cuniculus) (originally a non-target species), with no permanent consequences on a local, ancient population of wild goats (Capra hircus). Eradication on Pianosa, currently underway (started January 2017), is being performed by ground baiting, delivered by 4,750 dispensers placed on a 50 m × 50 m grid throughout the island. The latter operation is included in a multi-species eradication aimed at several other target species, among which was the brown hare (Lepus europaeus), apparently introduced around 1840. Genetic analyses on the ?rst trapped hares showed that this was the last uncontaminated and viable population of L. europaeus subsp. meridiei in existence. Whether of natural origin or introduced, the commencement of eradication of this population has instead created the awareness of a taxon otherwise unavailable for conservation elsewhere. While both projects address the same conservation issues (protection of shearwater colonies and restoration of natural communities), they di?er greatly regarding economic cost, public perception, e? ort needed to maintain results in the long term and e?ects on non-target species. In the present paper, speci?c attention has been paid to the comparison between bait delivering techniques, results obtained, the array of problems originating from the complex regulatory framework and reactions by the general public.

The history of the aerial application of rodenticide in New Zealand

Broome, K.

Garden, P.

McClelland, P.

Following the incursion of rats (Rattus rattus) on Taukihepa (Big South Cape Island; 93.9 km²) off southern New Zealand in 1963, and the subsequent extirpation of several endemic species, the New Zealand Wildlife Service realised that, contrary to general belief at the time, introduced predators do not reach a natural balance with native species and that a safe breeding habitat for an increasing number of at risk species was urgently needed. Off shore islands offered the best option for providing predator free habitat but there was a limited number of predator-free islands available and most were very small. Eradicating rodents on larger islands to provide a wider range and greater area of habitats was required and hand treating these larger areas using trapping and hand application of toxicants, the only methods available at the time, proved problematic and often impossible. Helicopters had been used to distribute bait for the control of rabbits and brushtail possums in the past but eradication of any particular predator species was considered not feasible. The development of a GPS-based aircraft guidance system, a suitable bait product, specialised bait delivery systems and second-generation anti-coagulant toxicants changed that. Now islands as large as South Georgia (3,900 km²) have been treated using this method

Successes and failures of rat eradications on tropical islands: a comparative review of eight recent projects

Brown, D.

Cranwell, S.

Cuthbert, R.J.

Griffiths, R.

Howald, G.

Keitt, B.

Pitt, W.C.

Tershy, B.

Wegmann, A.