In Mediterranean coastal areas, a common side effect of overfishing is a trophic cascade leading to sea urchin outbreaks. Uncontrolled by predators such as seabream, sea urchins overgraze marine forests, creating barrens - large unproductive areas of bare rock hosting very low biodiversity. This process negatively affects biodiversity and ecosystem services, and leads to a loss of nursery areas for commercially important fish. While certain solutions (e.g. harvesting) have been suggested, given the role of sea urchins as functional species, single-species fishery management measures (existing and under development in many areas) may fail to sufficiently capture ecosystem feedbacks.
In fact at present, knowledge and data about fishery-fish-sea urchins-marine forests systems are scattered and uncoordinated, with differences between areas and spatial scale. The MuMSUMed foresight workshop will therefore synthetize existing information to understand whether current knowledge is sufficient to develop simple fishery modelling tools for selected case studies, evidencing data gaps impairing the adoption of more advanced fishery modelling tools. The workshop will address the increasing necessity for a holistic management of coastal ecosystems to preserve marine forests for their ecological value while maintaining sea urchin populations, to guarantee the viability of artisanal fisheries relying on sea urchins and their predator fish. It will focus on developing comprehensive solutions for Mediterranean systems, integrating both scientific and end-users perspectives with a critical assessment of feasibility and desirability of outcomes.
The key objectives of MuMSUMed are to:
- identify the main mechanisms driving sea urchin dynamics and their relative importance (recruitment and predator control)
- discuss how these mechanisms interact with other components of the system, including predatory fish, marine forests, and fishery
- discuss and outline how these mechanisms and multispecies interactions can be integrated in an ecological model evaluating fishery management options
- Develop insights and feedbacks about the applicability of the proposed approaches informing about management requirement and needs
- Policy document on managing sea urchins and seabreams as fishery resources in light of their interactions, including a roadmap and suggestions for a management plan.
- Conceptual paper about managing fishery-fish-sea urchins-marine forests systems.
- Seeds for an international project proposal building up from the FWS.
This workshop will lay the foundations for a medium-term research strategy for management and conservation of a key coastal habitat in the Mediterranean Sea.