Northeast Atlantic Fisheries
- Increase in ocean temperature, extreme weather events, waves, rainfall and sea level rise.
- Increase in both Mackerel and Blue whiting biomass but reduction in Herring and changes in spatial distribution.
- Increased complexity in negotiations on allocations of shared stocks and overfishing.
- Increased fishery for Calanus finmarchicus due to vast increase in abundance and increased bycatch of fish larvae.
- Reduced deployment and performance of fishing gear, reduced safety at sea for crew and damage to ports and land-based facilities.
Effects of climate change
The main effects of climate change on the case study species is an increase in ocean temperature. In terms of total stock biomass, the effects are both positive and negative. Both the Mackerel and Blue whiting biomass are predicted to increase, while the Herring is more likely to reduce in numbers. Spatial distribution is predicted to change. That might pose a threat to the species as it might complicate negotiations regarding allocations of shared stocks and lead to overfishing. Finally, there is a possibility of increased bycatch of fish larvae, such as herring, with increased fishery of Calanus finmarchicus which is predicted to increase with increased temperature.
Risks and opportunities
The risk assessment identified three main drivers that can negatively or positively affect the NE Atlantic pelagic stocks. They are temperature, storminess and waves, increasing rainfall and sea level rise. The main opportunity identified is an increase in total stock biomass of mackerel due to increased sea temperature. Identified risks were more prominent than opportunities. Increased temperatures could lead to changes in spatial distribution of target species, increased fishery for Calanus finmarchicus due to vast increase in abundance and increased bycatch of fish larvae, such as herring, with Calanus fishery. Furthermore, it might increase complexity in negotiations on allocations of shared stocks and lead to overfishing of shared pelagic stocks due to unilaterally set quotas. Increased storminess and waves might cause reduced deployment and performance of fishing gear and reduced safety at sea for crew as well as damage to ports and land-based facilities due to weather conditions and sea level rise.
- Extensive research effort on both the spatial changes in routes and timing of migrations of target species and the effects of CC on these.
- Research on possible fishery for Calanus with regards to effects on the ecosystem, bycatches, gear and product development, potential necessity for area closures (seasonal and permanent) on important spawning and nursery areas for pelagic species.
- Optimizing fleet efficiency by facilitating the possibility of quota swaps or renting of quotas. The possibility should be available both between coastal states and between fleet categories.
- Framework for long term solutions on how to negotiate and allocate quota for species that change their distributional pattern due to climate change.
Atlantic mackerel, herring and blue whiting are extremely important species for the marine sector of multiple costal states in the North East Atlantic. Predicted changes in distribution due to climate change causes a number of socio-economic challenges, such as further increased complexity in negotiations on allocations of shared stocks which at present is causing severe overfishing. Creating a framework for negotiation that lead to long term solutions might prevent this evolution and lead to a more sustainable fishery of the pelagic species in the North East Atlantic. Furthermore, exploiting the opportunity of increased fishery of Calanus can have a significant, positive socio-economic effect as it would be a new resource for the economy.