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Corie Yanger

Publications and source records attributed to Corie Yanger.

2 recordsLinked to original sources

Wake Atoll: Evaluation of plant biosecurity

Introduced organisms can cause substantial effects across most landscapes. Island ecosystems, especially tropical islands, are at elevated risk from introduced organisms. The risks are even higher for tropical islands with moderate or high levels of transit, yet this can be minimized by application of appropriate biosecurity requirements. In this study, we examined the potential for non-native plant species introductions, especially invasive plants, via shipping containers to be transported to Wake Atoll, one of the most remote terrestrial land masses in the Pacific Ocean. We sowed debris collected from 30 shipping containers in a greenhouse experiment to determine if any live plants could be germinated, identify any species that germinated, and ascertain if they posed a threat if they were to be transported to Wake Atoll and became established there. During this study 23 plant species were identified, including ferns, monocots, and dicots. Fifteen of these species reached reproductive maturity over the course of seven months. From previous plant surveys on the atoll, we know that 13 of the 23 identified species were not previously recorded, and four species are already known to be invasive on Wake Atoll. This study provides insight into the potential for debris found in shipping containers to contribute to the spread of non-native, possibly invasive species. This information may help with the refinement of biosecurity strategies to prevent the accidental introduction of invasive species into sensitive natural areas such as Wake Atoll.

Hawaii Cooperative Studies Unit Technical Report

Decontamination of Ceratocystis pathogens responsible for rapid ʻŌhiʻa Death

Rapid ʻōhiʻa death (ROD) is caused by two recently described species of Ceratocystis , C. lukuohia and C . huliohia . These fungi are decimating ʻōhiʻa lehua ( Metrosideros polymorpha ), the keystone native tree species of Hawaiʻi. Viable Ceratocystis propagules can persist in ambrosia beetle frass (Coleoptera: Scolytinae), and movement of the frass may play a key role in the spread of the disease. In order to prevent the spread of ROD, we developed effective and practical surface (e.g., tools and shoes) decontamination methods to be used by researchers, managers, and the public alike. We first tested different household and laboratory disinfectants on the Ceratocystis fungi in culture, and then we applied the effective culture disinfectants to contaminated ambrosia beetle frass. Laboratory-grade ethanol (70, 80, and 95%), Clorox bleach (10%, 0.825% active ingredient [a.i.]), and isopropanol (70 and 91%), were all equally effective at decontaminating cultured C. lukuohia and C. huliohia. Although all concentrations of isopropanol (50, 70, and 90%) and ethanol (50, 70, and 90%) were effective disinfectants of Ceratocystis -contaminated frass, treatments of frass with up to 20% Clorox bleach (1.2% a.i.) were not completely adequate at killing the fungus. These data reveal that bleach is not a sufficient ROD disinfectant when frass is present, and isopropanol or ethanol are the more reliable options.

Hawaii