As of: 08/17/2021 12:12 p.m.
In the western Baltic Sea, the cod stocks have shrunk so much that they cannot recover for the time being. That emerges from a new study. The main reasons for this: climate change and overfishing.
According to a study, the cod stock in the western Baltic Sea has collapsed to such an extent that experts believe that a foreseeable recovery is unlikely. Researchers led by Christian Möllmann from the Center for Earth System Research and Sustainability at the University of Hamburg came to the conclusion that the tipping point for this population has been exceeded.
The team has analyzed decades of fisheries data in the region with the help of statistical models, the university announced. Scientists from Kiel University and the German Center for Integrative Biodiversity Research Halle-Jena-Leipzig were also involved. The study was published in the journal “Scientific Reports”.
Climate change and overfishing
The main reasons for the development are climate change and overfishing. “Due to the high catch quotas and previously neglected environmental factors, it is very unlikely that the cod population on the German Baltic coast will recover in the near future,” the statement said.
In fisheries management, a sustainable total biomass is determined annually for certain fish species that can be caught. So their existence can recover. “However, this system does not take into account the changing environmental conditions in the region, for example due to climate change.” Too much cod – called cod in other sea areas – has been caught in recent years.
Incorporate fewer fish
“Normally one assumes that the stocks can recover if the fishing pressure is reduced”, explained Möllmann. “Our analysis shows that this is probably no longer the case.” The fishing pressure combined with the warming of the water could have resulted in fewer fish being able to breed, so that fewer and fewer eggs survive. The cod stock will not recover at all or only very slowly.