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While invasive species eradications are at the forefront of biodiversity conservation, ant eradication failures are common. We reviewed ant eradications worldwide to assess the practice and identify knowledge gaps and challenges. We documented 316 eradication campaigns targeting 11 species, with most occurring in Australia covering small areas (b10 ha). Yellow crazy ant was targeted most frequently, while the bigheaded ant has been eradicated most often. Of the eradications with known outcomes, 144 campaigns were successful, totaling approximately 9500 ha, of which 8300 ha were from a single campaign that has since been partially re-invaded. Three active ingredients, often in combination, are most commonly used: fipronil, hydramethylnon, and juvenile hormone mimics. Active ingredient, bait, and method varied considerablywith respect to species targeted,which made assessing factors of eradication success challenging. We did, however, detect effects by active ingredient, number of treatments, and method on eradication success. Implementation costs increased with treatment area, and median costs were high compared to invasive mammal eradications. Ant eradications are in a phase of increased research and development, and a logical next step for practitioners is to develop best practices. A number of research themes that seek to integrate natural history with eradication strategies and methodologies would improve the ability to eradicate ants: increasing natural history and taxonomic knowledge, increasing the efficacy of active ingredients and baits, minimizing and mitigating non-target risks, developing better tools to declare eradication success, and developing alternative eradication methodologies. Invasive ant eradications are rapidly increasing in both size and frequency, and we envisage that eradicating invasive ants will increase in focus in coming decades given the increasing dispersal and subsequent impacts.

Microbenthos and macrobenthos were quantitatively studied at 62 stations distributed regularly over the Uvea Atoll lagoon (850 km2). Sampling was performed using both SCUBA and a 0.1 m2 Smith Mclntyre grab. Mean estimates of ATP, chlorophyll a and phaeopigments were 297.3ng/cm2, 77.01 mg/m2 and 35.28 mg/m2 respectively. The mean macrobenthic biomass was 4.14 gAFDW/m2 of which the macrophytobenthos accounts for 39%. The benthic biomass decreased from the coast to the deepest parts of the lagoon. Macrophytes were most abundant in the coastal area and became progressively scarcer with increasing depth. By comparison, sessile species dominated on hard substrates in intermediate and deep zones. The abundance of the surface-deposit feeder group, that dominated the trophic structure of zoobenthos (33% of the macrofauna biomass), could be explained by a microphytic biomass six times higher than macrophytobenthic one in terms of carbon. Carnivores (32%) were mainly represented by necrophagous species, and filter-feeders (27%) by bivalves. Herbivores were rare. Four main benthic communities were identified on the basis of their macrobenthic assemblages using a Detrended Correspondence analysis. They corresponded to (1) a coastal zone, with the highest mud percentage in sediments, (2) an intermediate zone, with moderate depth and dominated by hard substrates, (3) a back reef zone, with thick sand layers, and (4) a deep zone dominated by hard substrates. Relative distribution of the trophic groups varied according to the different zones and suggests distinct functional characteristics for the different benthic assemblages. From a biogeographic point of view, this study highlighted the richness of the Uvea Atoll lagoon in terms of benthic species and biomass, compared to other central Pacific atoll lagoons.