Understanding population connectivity and structure is crucial for advancing the sustainable management of commercially harvested species. While stable isotopes and elemental markers have revolutionised how we study animal movement, fractionation and biological processes can cause offsets between chemical values in the animal and environment, complicating data interpretation. Alternatively, radiogenic isotope systems (e.g. strontium) are prized for tracking the movement and origins of organisms and biological materials, because isotopic values in biological tissues directly reflect the isotopic value in the environment. However, strontium isotopes are only suitable for terrestrial and freshwater systems. A promising alternative for determining movement and provenance in marine species is neodymium isotopes but research on the application of this system is limited. We outline the incorporation and uptake of Nd in a range of marine animals and summarise methods for the extraction of Nd from animal tissues for isotopic analysis. Finally, we discuss about the use of commercial crab populations from Western Australia to understand the movement and connectivity crab populations using trace element and Nd isotope compositions. This research highlights cutting-edge technical analyses on a wide range of marine taxa and demonstrates potentially powerful markers in marine systems.