Cod and whiting in Danish waters (116190)

The project includes work on cod and whiting in Danish waters.

For cod:
The cod population in the Kattegat is in a poor condition, and the International Council for the Exploration of the Sea (ICES) recommends a total stop to fishing. However, a small bycatch quota for cod has been allocated, as cod is caught as bycatch in other fisheries, for example for Norway lobster and flatfish.

Studies have shown that cod in the Kattegat originate both from the local Kattegat population, which primarily spawns in the southern parts of Kattegat, and from the larger North Sea population, which spawns in the North Sea and where juveniles migrate into the Kattegat. It is important to know which cod are caught as bycatch in the Kattegat to help protect the local Kattegat population.

The project primarily aims to advise fisheries on how to best avoid bycatch of the vulnerable local cod population in the Kattegat. Therefore, we aim to collect information on the population of origin using genetic stock identification of cod collected from bycatch. The results will be used to develop recommendations directly to the fishery and will contribute to scientific advisory work at national and international levels.

For whiting:
The whiting population in Kattegat/Skagerrak is data-limited, leading to automatic reduction in advised fishing quotas based on precautionary principles implemented by ICES. Meanwhile, the whiting population in the neighbouring North Sea area is growing, resulting in a significant increase in advised fishing quota. The fishery in Kattegat/Skagerrak may be affected by the large North Sea population due to migrations of whiting from the North Sea and into the Kattegat/Skagerrak. Thus, the asynchronous development of quotas in the two adjacent areas may create challenges for the fishery in Kattegat/Skagerrak, which faces quota reductions despite potentially increasing influence from a large and growing North Sea population.

The current advice assumes that whiting in the North Sea and Kattegat/Skagerrak belong to different biological populations that do not mix across areas. However, little is known about the distribution and migrations of whiting populations and how these align with stock assessment and management areas. This project therefore aims to investigate whether whiting in the North Sea and Kattegat/Skagerrak belong to different biological populations. We will collect whiting from the neighbouring areas and compare their genetic fingerprints using DNA sequencing.

The project results will provide an overview of population distribution and advise the fishery on sustainable future development. Additionally, the results will contribute to biological advice at national and international levels.

Funding
The project is funded by Fiskeafgiftsfonden.

Research area: Population Genetics