The deep sea represents one of our planet's most enigmatic and ecologically significant regions, yet it remains vastly underexplored. Understanding deep-sea faunal biodiversity has become crucial for effective conservation and sustainable management as human activity increasingly impacts even the most remote marine environments. Environmental DNA (eDNA) sequencing and quantification offers an innovative, non-invasive method to explore these remote ecosystems. Still, its application in the deep sea faces unique challenges, including low eDNA concentrations and the extreme depths involved. This talk will discuss how transformative technologies and scientific advancements have addressed these challenges and pushed the boundaries of deep-sea biodiversity research. Recent innovations include the implementation of high-volume in situ eDNA sampling using in situ samplers capable of collecting comprehensive samples, significantly improving species detection compared to conventional methods. Introducing taxa-specific PCR primers has further enhanced the resolution of benthic biodiversity assessments, providing detailed insights into key deep-sea ecosystem engineers, such as octocorals and scleractinians corals. Comprehensive reference DNA barcode databases are now facilitating the accurate identification of deep-sea species, which is vital for understanding ecosystem structure and function. An empirical model for predicting eDNA degradation in marine environments reveals how temperature affects the persistence of eDNA and provides crucial insights for interpreting biodiversity data in both spatial and temporal dimensions. These achievements contribute to establishing foundational biodiversity baselines and creating tools necessary for ongoing monitoring and sustainable management of vulnerable deep-sea ecosystems. By leveraging cutting-edge eDNA technologies, we are well positioned  to inform policy and conservation efforts, ensuring these mysterious ecosystems remain protected for future generations.

Biological Oceanography,Molecular Ecology,Environmental DNA,Deep Sea