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Abstract. The Norway lobster, Nephrops norvegicus, is a valuable and commonly exported European decapod crustacean, which experiences stress from point of capture and onward transport. Stressors such as air exposure duration (i.e. emersion period) and air temperature have been studied previously. We investigated whether mortality could be reduced by decreasing road vibrations during transport, and how physiological stress measurements were influenced in a transport simulation experiment, reflecting a typical short road journey along a supply chain. Baseline haemolymph samples were taken from lobsters sampled immediately after commercial capture using static traps (lobster pots). Individuals were emersed for one hour, either immobile or with continuous shaking; the latter to simulate conditions occurring during transport. Both treatments significantly increased Total Haemocyte Counts (THC) and serum glucose, lactate and ammonium concentrations compared to baseline animals. Individuals subjected to continuous shaking showed higher glucose and ammonium concentrations compared to individuals maintained immobile. We conclude that shaking appears to influence the physiological responses of N. norvegicus in addition to the effects of emersion alone, and the reduction of road vibrations (e.g. via simple cushioning) can reduce post-transport mortality.

The Norway lobster, Nephrops norvegicus is a valuable European decapod, particularly when sold live, although along the supply chain lobsters experience a range of extreme stressors during and immediately after capture, and onward transportation. To improve quality and quantity of live product, laboratory experiments and transport simulations have investigated the effect of stress, particularly emersion and temperature, on physiology and the immune system, typically via blood (haemolymph) assays. This study investigated a relatively neglected stressor, physical trauma during transport (i.e. prolonged vibrations) via a simulated transport experiment, following anecdotal evidence that additional cushioning reduced post-transport mortality of N. norvegicus by up to ca. 20%. Baseline (BS) lobsters were sampled shortly after creel capture, and subsamples emersed for 1h, with additional experimental shaking (ES) or as immobile controls (EM). Both emersed treatments showed increased THC and serum glucose, lactate and ammonium, although serum protein and refractive index did not change significantly. Compared to the EM treatment, ES lobsters had significant increases in serum ammonium and glucose. In addition to emersion stress, physical trauma during transport is confirmed as an additional stressor that needs to be considered in transport simulations, whilst straightforward and cheap mitigation of physical trauma (e.g. road vibrations) could improve welfare, survival and recovery.