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Invasive alien species are a major threat to native insular species. Eradicating invasive mammals from islands is a feasible and proven approach to prevent biodiversity loss. We developed a conceptual framework to identify globally important islands for invasive mammal eradications to prevent imminent extinctions of highly threatened species using biogeographic and technical factors, plus a novel approach to consider socio-political feasibility. We applied this framework using a comprehensive dataset describing the distribution of 1,184 highly threatened native vertebrate species (i.e. those listed as Critically Endangered or Endangered on the IUCN Red List) and 184 non-native mammals on 1,279 islands worldwide. Based on extinction risk, irreplaceability, severity of impact from invasive species, and technical feasibility of eradication, we identified and ranked 292 of the most important islands where eradicating invasive mammals would benefit highly threatened vertebrates. When socio-political feasibility was considered, we identified 169 of these islands where eradication planning or operation could be initiated by 2020 or 2030 and would improve the survival prospects of 9.4% of the Earth’s 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 world’s nations.

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For threatened species with small captive populations, it is advisable to incorporate conservation management strategies that minimize inbreeding in an effort to avoid inbreeding depression. Using multilocus microsatellite genotype data, we found a significant negative relationship between genetic relatedness (inbreeding) and reproductive success (fitness) in a captive population of the critically endangered Black Stilt or KakīHimantopus novaezelandiae. In an effort to avoid inbreeding depression in this iconic New Zealand endemic, we recommend re‐pairing closely related captive birds with less related individuals and pairing new captive birds with distantly related individuals.

Japanese knotweed, Sakhalin knotweed, and their hybrid, Bohemian knotweed, are invasive across much of the United States. Monocultures formed by these species threaten natural riparian areas, and effective methods of control are being sought. Injection of herbicide is a relatively new control technique with no known published results. Bohemian knotweed was injected with four treatment dosages: 1 ml (0.03 oz) (0.48 g ae) (0.017 oz ae), 3 ml (0.10 oz) (1.44 g ae) (0.05 oz ae), or 5 ml (0.17 oz) (2.4 g ae) (0.08 oz ae) of undiluted glyphosate (suggested application), and 5 ml (0.17 oz) of a glyphosate : water mix (1 : 1, by vol) (1.2 g ae) (0.04 oz ae). Injections were tested at two heights on the plants: low node, 0.2 m (0.66 ft) (L) or chest height node, 1.0 to 1.3 m (3.3 to 4.3 ft) (M). After 1 mo, average percent injury was greater than 90%, and analysis showed no effect of injection location on the stem and no difference between the suggested 5-ml (0.17 oz) glyphosate application and 3-ml (0.10 oz) application. Nine months after treatment there was a reduction in knotweed height and density, though vigorous regrowth was evident within plots. Although the injection method results in the short-term dieback of injected stems, drawbacks to its use in certain scenarios should be considered when developing an integrated management plan for knotweed control.