Julia's research seeks to understand and predict how marine ecosystems respond to human-induced and environmental change. Her work has contributed to understanding how body size and other ecological traits affect the structure, dynamics and resilience of ecosystems and how this knowledge can be used to predict the ecosystem consequences of fishing and climate change, such as the loss of large predatory fish. She has developed dynamical size-structured models and indicators of the ecosystem effects of fishing at the global scale, regional scale (North Sea, Celtic Sea, North Pacific), and local-scale (coral reef and deep-sea fish communities) which have been used to inform indicators, targets and trade-offs for marine environmental management. Julia also has wide ecological and interdisciplinary research interests including comparison of terrestrial and aquatic food webs and fisheries and agriculture sectors. She is co-leader of the multi-model ensemble component of the NERC UK Marine Ecosystems Research Programme, is contributing to the Inter SectoraI Impact Model Inter-comparison Project (ISI-MIP) and the UK Marine Climate Change Impacts Partnership. Previously she was the coordinator of the ESF-funded 4 year research network SIZEMIC 'Body Size and Ecosystem Dynamics: Integrating pure and applied approaches from terrestrial and aquatic ecology to support an ecosystems approach' and was a council member of the British Ecological Society. She holds honorary positions at Imperial College London and University of Sheffield in the UK where she was previously based and is an associate editor for Journal of Applied Ecology and Ecology and Evolution.

Julia's research aligns with the University's research theme of Marine, Antarctic and Maritime. Her research areas include factors influencing the resilience of fish populations, marine communities and ecosystems (from shelf seas to deep seas), effects of climate change on marine ecosystems and global fisheries (historical data analyses and modelling future scenarios), and development of robust methods to support an ecosystem-based management (ecological models and indicators).