Observations on recent mass mortality events of marine mussels in the Oosterschelde, the Netherlands

• DOI: 10.1007/s10499-021-00713-6
• Publication Date: 2021-05-10T23:30:26Z
• Authors: Jacob J. Capelle; Ainhoa Blanco Garcia; Pauline Kamermans; Marc Y. Engelsma; Henrice M. Jansen
• Keywords: Bloom

Abstract Two mass mortality events (MMEs) of marine mussels that took place in the Oosterschelde, Netherlands—the first 2015/2016 and second 2019—both severely affected mussel production. The current study presents our observations on onset course both MMEs discusses probable putative causes. two displayed a distinct events. event started November 2015 with high rates culture plots, which remained elevated until autumn 2016. Approximately 40–50% from all age classes were lost plots 100% wild seed beds. April–May 2019 continued end July, ranging 20 to 100%, again classes. Culture areas other than Oosterschelde shellfish species not affected. Histological bacteriological screening produced no evidence for common pathogens or pollution as primary factor there is indication abnormal environmental conditions preceding during We hypothesize cumulation stressors results weakening rates. In 2019, this could be spawning activities (an unusual concentration larvae was found April) resulted very low condition April June, Phaeocystis bloom May prevented quick recovery, development granulocytomas up 60 70% live consequence cumulative stress. Although (single) causes identified, contributes knowledge fits wider disturbing trend shellfish.