Human well-being is dependent on ecosystem functioning and biodiversity, and it is not a surprise that maintenance of biological diversity and ecosystem services it provides is regarded as the most important part of European Biodiversity Strategy (Target 2, action 5). While conservation is the primary aim of MPAs they are also known to deliver a range of benefits to coastal communities and local marine sectors. Although there is evidence that MPAs attract visitors to coastal towns and beaches and over time increase fish stocks, MPAs are not warmly welcomed by all. However, effective communication of the evidence on the benefits to human wellbeing can be an important factor in their social and political acceptance. The ecosystem service perspective has the potential to make an argument for nature conservation as well as increase people’s understanding of their connectedness to the sea. From an ecosystem service perspective, the marine environment somewhat of a production chain, where species create communities and habitats which perform ecosystem processes and functions, which supply benefits to people such as fish for food. However, ecosystems ability to supply is not indefinite and environmental and natural resource mismanagement is most often the result of over or under estimation of the capacity of the ecosystem to provide. While all coastal and deep-sea habitats provide a range of services and benefits for people, the implementation of an MPA may result in an improvement in the quality or level of supply of an ecosystem service where pressures upon protected features are well-managed and reduced. MPAs are able to influence the levels of ecosystem service supply, the extent of influence is depending on the scale of the site, the listed features, and management processes. What’s more, understanding the portfolio of services provided by features within MPAs will improve planning and management, particularly in the context of making site-specific or regional trade-offs over designation, or in understanding the benefits and impacts of setting conservation objectives and introducing measures to achieve them.

The assessment of marine ecosystems service supply in the Latvian marine waters has already been done by partners of the LIFE REEF consortium as part of the BONUS BASMATI project. A new marine ecosystem service assessment tool already has been developed by LIAE, which links marine ecosystem components, functions and services (Armoskaite et.al., 2020). Currently, a quantitative assessment of ES supply used in tool is based on opinion of experts. Within the project activities quantitative data of benthic habitats will be obtained (field samples and mapping) allowing to operationalize the tool using habitat information from Latvian marine waters. A quantitative description of the relative importance of species and habitats in the supply of ecosystem services allows scenario analysis and improves our understanding of the impacts of decisions on the supply of ecosystem services. At the same time, the depiction of links allows the decision makers to understand the connectivity between the marine environment and human well-being. For instance, using this tool we are able to visually demonstrate how the degradation of mussel beds results in a decrease of supply in regulation and maintenance ecosystem services such as nutrient regulation which is critical to mitigating eutrophication and ensuring clean and transparent water for bathing. The result of the assessment will be used to organise all species and habitats according to the relative importance of their role in supply of ecosystem services. This will help us identify the hotspots of ecosystem service supply which should be considered at the top of the list for protection. At the same time, we will be able to identify the exact species responsible for the delivery of the service and trace back the pressures impacting them. This will provide support to strategic decision making in management ensuring appropriate measures are taken to mitigate pressures impacting the species within the MPAs. As result we will begin to better understand the core pressures impacting the MPAs and develop suggestions for management strategies, as well as provide biophysical and governance indicators for monitoring the effectiveness of the protection measures. It is expected that effectively managed marine protected areas will be safe heavens’ for species, and in turn boost levels of ecosystem service supply.