The potential implications of ghost gear: assessing the catch efficiency of unbaited pots in the Holderness crustacean fishery

Abstract Abandoned, lost or otherwise discarded fishing gear (ALDFG) is a significant global issue in marine environmental policy, with impacts including plastic pollution, habitat degradation and entanglement of marine fauna. Static gear, such as pots and traps can continue to attract and trap animals even if lost or abandoned, in a process known as ‘ghost fishing’. The ongoing efficiency of these ‘ghost pots’ is thought to be driven by a cycle where trapped animals die and effectively become fresh bait. However, little is known about the capacity for pots and traps to attract animals in the absence of bait, particularly in U.K. brown crab Cancer pagurus and lobster Homarus gammarus fisheries. In this pilot study, baited and unbaited pots were simultaneously deployed to determine relative catch rates of the latter. Overall, the unbaited pots had a catch rate of 34.6%, inclusive of bycatch relative to baited pots. Species specific relative catch rates were 55.5% and 47.5% for crab and lobster respectively. Furthermore, despite the mean size of both species being lower in the unbaited pots, 60% of crabs and 75.9% of lobsters exceeded escape gap dimensions. These findings suggest that ghost pots pose a substantial ecological and economic risk in this fishery and further work is urgently needed, both to validate these catch rates through increased sample sizes and to develop a nuanced understanding of pot loss rates in the region.