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Figuerola-Hernandez, C.E.

Griffiths, R.

Herrera-Giraldo, J.L.

Howald, G.R.

Keitt, B.

Silander, S.

Swinnerton, K.

Will, D.J.

The introduction of invasive rats, goats, and rhesus macaques to Desecheo National Wildlife Refuge, Puerto Rico led to the extirpation of regionally signifi cant seabird colonies and negatively impacted plant and endemic reptile species. In 2012, following the successful removal of goats and macaques from Desecheo, an attempt to remove black rats using aerially broadcast rodenticide and bait stations was unsuccessful. A review of the operation suggested that the most likely contributors to the failure were: unusually high availability of alternative foods resulting from higher than average rainfall, and insufficient bait availability. In 2016, a second, successful attempt to remove rats was conducted that incorporated best practice guidelines developed during a workshop that focused on addressing the higher failure rate observed when removing rats from tropical islands. Project partners developed a decision-making process to assess the risks to success posed by environmental conditions and established go/no-go decision points leading up to implementation. Observed environmental conditions appeared suitable, and the operation was completed using aerial broadcast of bait in two applications with a target sowing rate of 34 kg/ha separated by 22 days. Application rates achieved on the ground were stratified such that anticipated high risk areas in the cliff s and valleys received additional bait. We consider the following to be key to the success of the second attempt: 1) monitoring environmental conditions prior to the operation, and proceeding only if conditions were conducive to success, 2) reinterpretation of bait availability data using the lower 99% confidence interval to inform application rates and ensure sufficient coverage across the entire island, 3) treating the two applications as independent, 4) increasing the interval between applications, 5) seeking regulatory approval to give the operational team sufficient flexibility to ensure a minimum application rate at every point on the island, and 6) being responsive to operational monitoring and making any necessary adjustments.

The eradication of black rats (Rattus rattus) from Dog Island, Anguilla, using ground-based techniques

Bell, E.

Connor, R.

Daltry, J.

Mukhida, F.

Varnham, K.

Rat eradication techniques developed in New Zealand are a proven method for removing invasive rodents from islands worldwide. This technology moved rapidly from ground-based bait station operations to aerial application of rodenticides. Rat eradications on tropical islands using similar methods, have not always been as successful as those in temperate regions. As most previous eradications in the Caribbean have been on islands smaller than 50 ha, the eradication of black rats (Rattus rattus) from 207 ha Dog Island was a significant increase in size. Reptile and seabird populations on Dog Island had been in decline for a number of years and black rats were identified as the most likely factor. Following the feasibility study in 2007, the Dog Island Recovery Project was launched in 2011. This was a multiple-year project incorporating a ground-based eradication with establishment of biosecurity procedures to prevent reinvasion, alongside long-term monitoring of native species. Bait stations with cereal-based wax blocks containing brodifacoum at 0.005% w/w were established on a 3050 m grid over the island. Interference with bait stations by non-target invertebrates, particularly crabs, was high and bait stations required moving or elevating to avoid this. However, there was no evidence of any non-target animals being killed or injured by the bait. Eradication success was confirmed in 2014.

Recovery of introduced Pacific rats following a failed eradication attempt on subtropical Henderson Island, South Pacific Ocean

Bond, A.L.

Churchyard, T.

Cuthbert, R.J.

Duffi eld, N.

Havery, S.

Kelly, J.

Lavers, J.L.

McClelland, G.T.W.

Oppel S.

Proud, T.

Torr, N.

Vickery, J.A.

Rodent eradications in tropical environments are often more challenging and less successful than those in temperate environments. Reduced seasonality and the lack of a defined annual resource pulse influence rodent population dynamics differently than the well-defined annual cycles on temperate islands, so an understanding of rodent ecology and population dynamics is important to maximise the chances of eradication success in the tropics. Here, we report on the recovery of a Pacific rat (Rattus exulans) population on Henderson Island, South Pacific Ocean, following a failed eradication operation in 2011. We assessed changes in the rat population using capture rates from snap-trapping and investigated seasonality by using capture rates from live-trapping. Following the failed eradication operation in 2011, rat populations increased rapidly with annual per capita growth rates, r, of 0.485.95, increasing from 6080 individuals to two-thirds of the pre-eradication abundance within two years, before decreasing (r = -0.25 -0.20), presumably as the population fluctuated around its carrying capacity. The long-term changes in rat abundance may, however, be confounded by short-term fluctuations: four years after the eradication attempt we observed significant variation in rat trapping rates among months on the plateau, ranging from 36.6 rats per 100 corrected trap-nights in mid-June to 12.6 in late August. Based on mark-recapture, we also estimated rat density fluctuations in the embayment forest between 20.4 and 42.9 rats ha-1 within one month in 2015, and a much lower rat density on the coral plateau fluctuating between 0.76 and 6.08 rats ha-1 in the span of two months. The causes for the short-term density fluctuations are poorly understood, but as eradication operations on tropical and subtropical islands become more frequent, it will be increasingly important to understand the behaviour and ecology of the invasive species targeted to identify times that maximise eradication success.

How the race to achieve Aichi Target 11 could jeopardize the effective conservation of biodiversity in Canada and beyond.

BRB

Lemieux, C J

n 2010 Parties to the United Nations (UN) Convention on Biological Diversity (CBD) agreed to reduce the rate ofbiodiversity loss within a decade by achieving 20 objectives that are commonly known as the Aichi Targets.

Widespread shortfalls in protected area resourcing undermine efforts to conserve biodiversity.

BRB

Protected areas (PAs) are a key tool in efforts to safeguard biodiversity against increasing anthropogenic threats. As signatories to the 20112020 Strategic Plan for Biodiversity, 196 nations pledged support for expansion in the extent of the global PA estate and the quality of PA management.

Traditional knowledge of weather and climate in the Pacific.

Climate Change Resilience

Increasing Community Resilience to Climate Extremes and Natural Disasters. By closely observing their local environment, communities in the Pacific have developed skills that enable them to build coping strategies for extreme weather and climate events. They are able to make their own predictions for weather and climate variables based on traditional knowledge that has evolved through observation and experience over a considerable period of time.

Integrating three-dimensional benthic habitat characterization techniques into ecological monitoring of coral reefs.

Burns, J H R

Craig, B K

Fukunaga, Atsuko

Kosaki, R K

Long-term ecological monitoring of reef fish populations often requires the simultaneous collection of data on benthic habitats in order to account for the effects of these variables on fish assemblage structure.

Globally important islands where eradicating invasive mammals will benefit highly threatened vertebrates

BRB

Holmes, Nick D [et al.]

Earths most highly threatened terrestrial insular vertebrates (111 of 1,184 species). Of these, 107 islands were in 34 countries and territories and could have eradication projects initiated by 2020. Concentrating efforts to eradicate invasive mammals on these 107 islands would benefit 151 populations of 80 highly threatened vertebrates and make a major contribution towards achieving global conservation targets adopted by the worlds nations.

South Africa works towards eradicating introduced house mice from sub-Antarctic Marion Island: the largest island yet attempted for mice

Beaumont, J.

Chauke, L.F.

Chown, S. L.

Cooper, J.

Devanunthan, N.

Dilley, B.J.

Dopolo, M.

Fikizolo, L.

Heine, J.

Henderson, S.

Jacobs, C.A.

Johnson, F.

Kelly, J.

Makhado, A.B.

Marais, C.

Maroga, J.

Mayekiso, M.

McClelland, G.

Mphepya, J.

Muir, D.N. Ngcaba, N. Ngcobo, J.P. Parkes, F. Paulsen, S. Schoombie, K. Springer, C. Stringer,H. Valentine, R.M. Wanless and P.G. Ryan

Preston, G.R.

House mice (Mus musculus) were introduced to South Africas sub-Antarctic Marion Island, the larger of the two Prince Edward Islands, by sealers in the early 19th century. Over the last two centuries they have greatly reduced the abundance of native invertebrates. Domestic cats (Felis catus) taken to the island in 1948 to control mice at the South African weather station soon turned feral, killing large numbers of breeding seabirds. An eradication programme finally removed cats from the island by 1991, in what is still the largest island area cleared of cats at 290 km2. Removal of the cats, coupled with the warmer and drier climate on the island over the last half century, has seen increasing densities of mice accumulating each summer. As resources run out in late summer, the mice seek alternative food sources. Marion is home to globally important seabird populations and since the early 2000s mice have resorted to attacking seabird chicks. Since 2015 c. 5% of summer-breeding albatross fledglings have been killed each year, as well as some winter-breeding petrel and albatross chicks. As a Special Nature Reserve, the Prince Edward Islands are afforded the highest degree of protection under South African environmental legislation. A recent feasibility plan suggests that mice can be eradicated using aerial baiting. The South African Department of Environmental Affairs is planning to mount an eradication attempt in the winter of 2021, following a partnership with the Royal Society for the Protection of Birds to eradicate mice on Gough Island in the winter of 2020. The eradication programme on Marion Island will be spearheaded by the South African Working for Water programme Africas biggest conservation programme focusing on the control of invasive species which is already driving eradication projects against nine other invasive species on Marion Island.

Improving the efficiency of aerial rodent eradications by means of the numerical estimation of rodenticide density

Aguirre-Muñoz, A.

Méndez-Sánchez, F.A.

Rojas-Mayoral, B.

Rojas-Mayoral, E.