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Impact of bottom gear fishing is primarily determined by the sensitivity of the benthic community, fishing intensity and penetration depth of the gears. Disturbance of benthic populations and physical modification of bottom substrates are "outputs" of bottom fishing, which produces a clearly defined footprint identified by the spatial extent of fishing and the width of the gear that is in contact with the sea floor. Solutions and innovations to reduce the adverse impacts of bottom fisheries on demersal ecosystems is a global priority. Three modus operandi were studied - alternative gears, alternative catch stimuli, alternative gear components, where each could contribute to a reduction in fishing footprint, benthic impact, sediment resuspension. A collaborate study was undertaken with the fishing industry into innovative technologies to reduce seabed fishing impacts in ten case studies covering the main mobile bottom-contacting gears across European waters. Strategies to reduce fuel use, greenhouse gas emissions, and bycatch are explored in the study as incentives for the fishing industry to reduce seabed impacts. Lifting otterboards or replacing mechanical- by electrical-stimulation provide promising avenues to mitigate fishing impact. Replacing towed- by static-gear has potential but is not a generic solution. The adoption of technical innovations critically depends on the economic performances. In some cases, reduced fuel consumption and costs enhanced the uptake by the fishery. In certain scenarios, limited fishing opportunities due to unacceptable environmental impacts, has prompted innovation. No single modus operandi can solve all the seabed impacts and a combination may be most effective depending on local habitat type, regulatory setting, social and economic characteristics of the fishery. As demonstrated by the current study, creative and innovative solutions can be found to minimize the effects of fishing on marine habitats while maintaining viable, long-term commercial fisheries. [ABSTRACT FROM AUTHOR]

Stocks of Atlantic cod (Gadus morhua) in the Baltic Sea, Kattegat and Skagerrak (N. Europe) have been strongly exploited for decades bringing them into an enduringly depleted status. Scientific cod stock related advice for targeted and mixed fisheries is provided on an annual basis by the International Council for Exploration of the Sea. This advice forms a basis for ministerial decisions on, e.g., the total allowable catch and management plans. Despite measures to reduce fishing-induced mortality of cod, such as catch and effort restrictions, increased gear selectivity, closed areas and seasons, clear signs of recovery are yet to be seen. Thus, traditional advice for the management of these stocks may have to be complemented by advice on supporting measures focusing on other pressures hampering the recovery of cod. The present study elaborates on potential supportive measures for cod stock recovery in the Baltic Sea, Kattegat, and Skagerrak (including local populations where applicable), based on current knowledge. The list of measures presented here is the outcome of in-depth discussions on the state-of-the-art knowledge, among cod experts and further with stakeholders with the aim to follow principles of ecosystem-based fisheries management. Following the identification of different pressures on and prerequisites for the separate stocks, the listed measures differ between stocks and include cod bycatch mortality reduction, alterations in fisheries affecting food sources for cod, restocking, protection of juvenile habitats, and reduced predation. The literature review and the list of measures are intended to provide decision-support for managers and policymakers aiming to provide conditions for the cod stocks to recover. [Display omitted] [ABSTRACT FROM AUTHOR]

Pedersen, S. A., Fock, H., Krause, J., Pusch, C., Sell, A. L., Böttcher, U., Rogers, S. I., Sköld, M., Skov, H., Podolska, M., Piet, G. J., and Rice, J. C. 2009. Natura 2000 sites and fisheries in German offshore waters.–ICES Journal of Marine Science, 66: 155–169. The principal objective of sites selected as part of Natura 2000 is to achieve or maintain a favourable conservation status of habitats and species named in the EU Birds and Habitats directives. In the German exclusive economic zone, the habitat types protected by this legislation are sandbanks and reefs; protected species include marine mammals, seabirds, and specific migratory fish species. The ICES project Environmentally Sound Fishery Management in Protected Areas (EMPAS) aims to answer two questions: (i) To what extent do specific fishing activities significantly threaten attainment of the conservation objectives of the Natura 2000 sites? (ii) What management measures would reduce these conflicts and how effective would they be at helping to ensure the favourable condition of these sites? Assessments of fishing impacts on Natura 2000 sites require basic data on the conservation status of individual habitats and species, as well as data for fine-scale distributions of ongoing fishing activities. This paper describes and discusses the process used by the EMPAS project in developing fishery-management plans for each Natura 2000 site in German offshore waters. [ABSTRACT FROM PUBLISHER]

This study investigates six areas in a historically heavily trawled region of the southern Baltic Sea. Using acoustic geophysical mapping data and sediment cores from three field campaigns (2019, 2020, 2023), we evaluate and quantify the cumulative physical impacts from bottom trawling and the influence of seabed geology on mapped trawl tracks. The results are compared with fishing intensity data over three periods; 2012–2016, 2017–2019 and after the fishery closed. A correlation between fishing intensity and density of mapped trawl tracks exists in the soft sediments of the northern part of the area, while this link is weak in the less trawled southern part, where the seabed is characterized by more consolidated glacial clays and the high density of mapped trawl tracks reflects the preservation of tracks >8 years old. Four years after the closure of the fishery there were no signs of trawl-track degradation in any of the areas. In summary, mapped track densities alone are not a suitable measure of trawling intensity, considering the influence of seabed geology and the persistence of trawl tracks over time. Sediment deformation, observed by CT-scanning, indicates extensive remoulding and coarsening of the upper 20–40 cm of sediments in the trawled areas. • Seafloor geology affects appearance and preservation of otter trawl tracks. • Trawl tracks can be acoustically visible either in bathymetric or backscatter data. • Trawl tracks may be > 8 years old. • Acoustically mapped track density alone is not a good measure of fishing intensity. • Trawled sediments display extensive deformation and coarsening in the upper 20–40 cm. [ABSTRACT FROM AUTHOR]