Future directions for the detection of marine pests

Marine pests cause ecological and economic harm through loss of biodiversity, reduction in revenue from aquaculture and fisheries, damage to infrastructure, loss of amenity and, in some instances, human health impacts.... [ view full abstract ]

Marine pests cause ecological and economic harm through loss of biodiversity, reduction in revenue from aquaculture and fisheries, damage to infrastructure, loss of amenity and, in some instances, human health impacts. Managing impacts of established pest species requires ongoing measures, leading to a significant economic burden, and early detection is required to facilitate successful eradication. Australia’s National System for the Prevention and Management of Marine Pest Incursions requires regular surveys of specified ports around Australia to detect new incursions and range expansions of priority pest species. Surveillance data will also inform decisions about proposed domestic ballast water arrangements, and policy on marine pest management. Traditional surveys are labour intensive, expensive, and require access to taxonomic expertise. Molecular surveys can be rapid, and are less expensive than traditional surveys. A molecular survey of Port Adelaide detected all pests known to occur in the area for which assays were available, including one not detected by simultaneous traditional surveys. Additional validation is needed, however, before molecular methods can be more widely used. Issues with molecular methods applied to environmental samples can include inhibition of assays leading to unreliable detection, or cross-amplification of non-target species. There is a lack of understanding of how DNA concentration relates to the population size of pest species, and of effective detection limits in environmental samples. Molecular methods are currently available for eight priority pest species, including Undaria pinnatifida, Asterias amurensis and Sabella spallanzanii, but there are no tests yet for the majority of the 55 priority pests. This presentation will discuss the work currently underway to address these issues and to validate molecular methods for use around Australia, and examine future directions for detecting marine pests using genetic techniques, including next generation sequencing.