Stress and mortality in the supply chain of live scallops Pecten maximus L., fr...

Stress and mortality in the supply chain of live scallops Pecten maximus L., from scuba diver to market


Snorre Bakke


Aquaculture Research







Here, we report results from a project where the aim was to study stress and mortality in the supply chain from harvest to market for live scallops Pecten maximus L., hand-picked by scuba divers. With experiments conducted both during the warm (September) and cold (April) seasons, emphasis was put on how mechanical influence, stacking height, post-harvest water storage and dry transport affected scallop fitness. When scallops were exposed to mild- or hard mechanical shocks (dropped three times from 50 or 150 cm), it was found that hard mechanical shock caused up to 90% mortality during subsequent water storage. Results from the experiments where scallops were stored at different stacking heights (15, 30 and 50 cm) in water showed that both the duration of storage and the stacking height had a significant effect on mortality. Higher stacking heights also affected survival in subsequent transport. For long-term storage (>7 days), it is recommended to limit the stacking height of scallops stored in tanks to reduce risk of mortality. Respiration experiments showed an average oxygen consumption of 0.10 and 0.24 mg O2 min1 kg1 f.w. in the cold and warm season respectively. Water supply during storage of scallops should be adjusted to water temperature and biomass. Registration of mortality and analysis of the Adenylic Energy Charge of scallops followed through the production cycle from harvest to market indicate that it is the sum of stressors that are determinable for final survival.