Monday October 17, 2022
Technology Networks —
The first ecosystem model that covers the complete food web of the western Baltic Sea predicts how marine life in the region would react to different fisheries scenarios and additional human-induced stressors. The model simulations reveal that ecosystem-based fisheries management would restore stocks of commercially relevant fish species and the endangered harbour porpoise population. Marine life would become more resilient, and options for additional carbon sequestration would open up, a team of marine scientists led by GEOMAR Helmholtz Centre for Ocean Research Kiel (Germany) explains in a study now published in Frontiers in Marine Science.
Decades of overfishing, together with nutrient pollution, rapid increase in hypoxia, ocean warming and acidification have put fish and harbour porpoise (Phocoena phocoena) in the western Baltic Sea at risk of collapse. But the commercially relevant stocks of cod (Gadus morhua), herring (Clupea harengus) and sprat (Sprattus sprattus) can be restored and prospects for marine mammals be improved, according to a team of marine scientists from GEOMAR Helmholtz Centre for Ocean Research Kiel (Germany), the German Federal Agency for Nature Conservation (Bundesamt für Naturschutz, BfN, Germany) and the Institute of Biosciences and Bioresources at the National Research Council (CNR) of Italy.
Using model simulations, the researchers tested five scenarios from no fishing to ecosystem-based fisheries management. This approach accounts for the roles of species within their ecosystem and adjusts catches accordingly to keep fish stocks in a healthy, productive and resilient condition. A study now published in the scientific magazine Frontiers in Marine Science concludes: Ecosystem-based fisheries management would allow the endangered harbour porpoise population to recover and increase catches of herring and cod significantly within a decade. The food web would become less susceptible to eutrophication and climate change and, in addition, more able to support carbon sequestration than in a business-as-usual scenario that assumes today’s fisheries practices continue.