Anguillid eels are globally distributed in temperate, tropical, and subtropical areas. Numerous anguillid species are under threat globally, and a better understanding of their life history is needed. A critical stage in their life cycle is the migration of mature adults from freshwater habitats and estuaries to tropical marine spawning grounds. For many anguillids, especially those in the southern hemisphere, mystery still shrouds their spawning migrations. This talk presents a series of case studies on the migration behaviours of adult eels from coastal river systems in Victoria, south-east Australia. Eels were tagged using acoustic and pop-up satellite archival tags, and their movements monitored throughout freshwater habitats and the marine environment. We explore the environmental drivers associated with the downstream migration of tagged eels in freshwater habitats, including links to water levels/river flow, and their vertical movement behaviour, migration routes, and predation in the ocean.