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Invasive rodent eradications are one of the most effective conservation interventions to restore island ecosystems. However, achievements in the tropics are lagging behind those in temperate regions. Land crab interference in bait uptake has been identified as one of the main causes of rodent eradication failure on tropical islands, but the issue of effective mitigation of bait loss due to land crab consumption is poorly understood. For example, there are over 100 species of land crab and each may behave differently. We reviewed the available literature to answer: (1) which crab species are the most problematic? (2) what mitigation measures have been effective? and (3) how do invasive rodents impact land crab communities? We analysed a systematic dataset from six tropical islands to test two hypotheses: (a) bait uptake is highest when burrowing (Brachyura) land crabs are present; and (b) small land crabs (including juveniles of the larger species) are highly vulnerable to rodent predation. We found that large species (e.g. genera Cardisoma, Johngarthia and Birgus) are the most problematic during rodent eradications. Effective mitigation measures to prevent bait loss include using higher bait application rates and conducting eradications during the driest months. Land crab communities tend to go through significant changes after rodent removal. From our analyses, we confirmed pre-eradication data are valuable for eradication planning, as seasonality and type of crab can influence outcomes. Post- eradication data confirmed small crab species ( 60 mm) are highly vulnerable to rodent predation. More effort should be invested into monitoring land crabs in tropical latitudes, particularly to determine any biogeographic or taxon trends in land crab interference. Land crabs are key for the restoration of the islands, as they shape ecosystems through their role as ecosystem engineers, hence they are excellent indicators of ecosystem recovery. Our results will contribute to the better planning of future rodent eradications on tropical islands where land crabs are significant bait competitors.

Efforts to remove invasive rodents (e.g. Rattus spp. and Mus musculus) from islands often use toxicant-laced baits containing the anticoagulants brodifacoum or diphacinone. Rodenticide baits are generally delivered through aerial- or hand-broadcast, or in bait stations. These baits are not rodent-species and are subject to non-target consumption or secondary exposure (e.g. an individual preying upon another individual that has consumed bait). During rodenticide applications, it is generally unknown which animals are visiting and consuming bait; and to quantify this, we recommend using trail cameras (e.g. Reconyx™ motion-activated infra-red) positioned to monitor individual bait pellets. To demonstrate the importance and effectiveness of using trail cameras during such operations, we report results of target (Rattus rattus, black rat) and non-target (native land crab, lizard, insect) bait-interactions after an aerial-broadcast of Brodifacoum-25D Conservation to eradicate rats from Desecheo Island, Puerto Rico. During the ?rst ?ve days following bait application, trail cameras (n = 15) revealed that there were 40 incidences of animals contacting bait pellets: 50% rat, 32% hermit crab, 13% Ameiva lizard, and 5% insect. Trail cameras provide temporal and spatial information regarding the e?ectiveness of rodent removal, and the last rat pictured by trail cameras on Desecheo was six days after bait application began. Trail cameras revealed 30 incidences of animals contacting bait pellets 6–20 days after bait application began: 47% hermit crab, 37% Ameiva lizard, 13% insect, and 3% black crab. Despite viewing ~69,000 images from trail cameras, lizards were never pictured consuming bait on Desecheo; therefore, any brodifacoum exposure to Desecheo lizards likely occurred via secondary pathways (e.g. consumption of contaminated insects). Scaling up, we estimate that > 75% of the total bait distributed on Desecheo was not consumed by rats. Trail cameras help inform the hazards of rodenticide use and can be easily incorporated into rodent removal operations.

Support for Pacific stance at Bonn climate round.

The careful release protocols presented here describe the tools and techniques for safely removing fishing gear from incidentally captured sea turtles (Plate C-1) and other bycatch species.

The British Ecological Society is the largest ecological society in Europe, in terms of our membership and the wide range of services and activities we provide.

Over the last decade, marine spatial planning (MSP) has become an increasingly accepted approach to achieve multiple objectives for ocean management.

Tropical coral reefs currently face an unprecedented restructuring since their ex-tant form and function emerged ~24 million years ago in the early Neogene.

Coral reefs underpin a range of ecosystem goods and services that contribute to the well-being of millions of people

NZPPOA project has selected Nanikaai village as its Kiribati pilot site. This was based on the endorsement made by Kiribati Government. Baseline assessment of Nanikaai was completed in March by the Ministry of Fisheries and Marine Resources Development and the results will be shared at the follow up workshop in April (2019).

Tokelau Government has confirmed and selected all its three atolls as the pilot site for the New Zealand Pacific Partnership Ocean Acidification (NZPPOA) project.