SEAwise synthesis of predicted impacts of changes in habitat and spatial management measures suggested in SEAwise for online tool
The SEAwise project works to deliver a fully operational tool that will allow fishers, managers, and policy makers to easily apply Ecosystem Based Fisheries Management. This SEAwise report synthesizes all spatial aspects of stocks and fisheries spanning from environmental drivers to habitat change and management options.
After a first round of investigation of available tools for predicting the impact of various spatial management options on fisheries distribution, yield, profitability, and selectivity, SEAwise focused on putting to the test spatial scenarios to capture the medium/long term effects of ecological and fisheries uncertainties with a dynamic modelling approach, deploying spatial bioeconomic models. This allowed for assessing potential changes in fishing effort such as new regulatory or ecological conditions.
Medium to long-term projections, accounting for (among others), the effects of climate change (IPCC scenarios), as well as hot-spots of commercial species (spawning/nursery grounds) and vulnerable marine life (benthos, seabirds, marine mammals, sea turtles, corals), have evaluated the feasibility of several fisheries spatio-temporal closures in the real world.
The fisheries considered were specifically:
- Demersal fisheries operating in Western Waters (Bay of Biscay), including vessels from Spain and France;
- Demersal fisheries operating in Western Waters (Celtic and Irish Sea), including vessels from Belgium, Germany, Spain, France, Ireland and England;
- Pelagic fisheries operating in Western Waters (Bay of Biscay), including vessels from Basque Country;
- Demersal fisheries operating in North Sea, including vessels from Belgium, Denmark, England, France, Scotland, Germany, Nederland, Scotland and Sweden;
- Demersal fisheries, operating in Central Mediterranean Sea (Adriatic and Western Ionian Sea), including vessels from Italy, Croatia, Slovenia, Albania and Montenegro;
- Demersal fisheries, operating in Eastern Mediterranean Sea (Eastern Ionian Sea), including vessels from Greece;
- Trawl fisheries operating in the Western Baltic Sea, including vessels from Denmark, Sweden, and Germany.
The scenarios investigated in SEAwise suggest that prohibition of certain fishing practices, not only in currently designed MPAs but also in fit-to-purpose areas to limit the risk of incidental species and the degradation of benthic status, will significantly impact the overall fisheries economy and fish populations. These fit-to-purpose areas need to be explicitly designed to safeguard vulnerable stages for exploited stock, bycatch risk of unwanted species, and sensitive benthic habitats while improving spatial and gear selectivity. Such spatial conservation measures will induce negative short-term effects on the fisheries (e.g.: decreased catches and increased operating costs due to effort displacement to surrounding or distant areas) as well as potentially harmful counterproductive effects on biodiversity in some occurrences. However, these may eventually be balanced out over the long term if stock and ecosystem recovery is accounted for.
SEAwise highlights that spatial management should be applied complementary to existing non-spatial management measures (e.g.: effort restrictions, quotas, technical measures), and of course proper governance and incentives to limit the resistance to change. It is worth mentioning that in the long term, a changing climate could be overwhelmingly affecting fish and fisheries' productivity and the marine ecosystems at large, suggesting that more drastic conservation measures may be needed.
