The UK's expanding global reach for seafood over 120-years.

Seafood markets have become increasingly internationalised over the course of the twentieth century, induced by expanding footprints of fishing fleets, improved communication and transport infrastructure, and trade agreements. We compiled archival UK seafood import data from UK Government, SEAFISH and FAO sources to track the expansion of the UK's global reach for seafood products from 1900 to 2020. UK domestic fisheries landings declined from the 1970s following overexploitation and regulatory reforms, leading to a growing dependence on fish catches outside national waters and the international seafood trade-network. The volume of reported seafood imports increased by 6.4-fold from 1900 to 2020, overtaking domestic landings in 1985, with the species composition of these imports reflecting the palette of UK consumers, i.e., for the 'big 5' of cod, haddock, salmon, tuna and prawns, alongside agri/aquaculture industry demands for fishmeals/oils. The number of reported countries from which the UK imported seafood increased from five in 1900 to eighty-nine in 2020, covering all continents. The average distance seafood was imported increased by between 18 and 32%, from 2980 km (1900) to ~ 3520-3940 km (2020) (UK Government and SEAFISH data respectively), demonstrating the increasing geographic spread of UK demand. These results accentuate the need for stringent domestic fisheries management to recover local fish stocks, consumer diversification beyond the 'big 5', and for improved collaborative international fisheries governance to mitigate the potential for serial depletion of popular food fish. Graphical abstract: Supplementary Information: The online version contains supplementary material available at 10.1007/s11160-025-09942-x.