The European Tracking Network: one decade of united efforts to advance aquatic conservation in Europe

Acoustic tracking has become an essential tool for studying the spatial ecology of aquatic animals, playing a crucial role in informing management and conservation efforts (Crossin et al. 2017; Hussey et al. 2015; Alós et al. 2022). Over the past two decades, several large-scale tracking networks have been established worldwide, fostering collaboration among researchers and upscaling the deployment of wide-ranging monitoring arrays on marine and freshwater environments. These networks provide key information to investigate key aspects of the population dynamics and behaviour of transnational aquatic species in relation to their environment to feed policies and directives at multiple scales.The European Tracking Network was launched in 2015 to unite the aquatic animal tracking community in Europe with the mission to track aquatic animal to better understand, protect and manage them. It is a timely initiative that fits withing the UN Ocean Decade and the EU Mission Ocean, which aims to restore our Ocean and Waters and provides significant contributions to several EU directives. In this decade, ETN has grown from an initiative of 20 scientists to become a sustainable network of over 620 researchers representing almost 170 institutions, with a central data system and research infrastructure across Europe including four acoustic telemetry arrays implemented at key straits in Europe; growing collaborative research on a multitude of species and environments; and substantial capacity building.ETN has five main principles that connect the members and allow them to independently implement specific actions on local-to-regional scales that serve the overall objectives of the network and strengthen the grassroots collaboration, ensuring a sustainable, flexible, compatible, and impactful network. In this talk we will showcase the benefits of large-scale aquatic telemetry initiatives by highlighting some case studies on each of the ETN principles and we will explore the growing potential for ETN to inform biodiversity monitoring and decision-making bodies using relevant metrics.