Iroise Marine Natural Park

Summary

The topic studied was the ecosystem services provided by kelp forest habitats. The management of Laminaria hyperborea exploitation, the most abundant kelp species, has been implemented and negotiated 15 years ago by kelp harvesters. In a context of increasing demand for kelps, the main objective, through the ecosystem services assessment approach, was to provide new insights to the current management debate, and for the search of new trade-offs. The aim is to achieve precise management of the kelp field that allows a sustainable yield and employment for fishermen, while protecting patrimonial species as Bottle-nose dolphin and mitigating impacts on other uses.

A. Maulpoix / CNRS

For additional information

Date: 2012-2015

The work presented here has been developed in six case studies of the VALMER Interreg 4A Channel project (2012-2015).

Coordination by M. Philippe, J. Ballé-Béganton and D. Bailly
based on written contributions from A. Vanhoutte-Brunier, P. Le Nilliot, R. Mongruel, A. Marzin, M. Laurans, O. Guyader, D. Davoult and D. Vaschalde

Site description

The Molène’s archipelago is a shallow area of almost 300 km² where are found the most diversified European algae Laminaria fields and the French’s most extensive ones. This area is remarkable due to the outstanding natural ecosystem containing dozens of species of algae, marine mammals and birds of national and European interest.

This archipelago is included in the Parc naturel marin d’Iroise boundaries, a marine protected area created in 2007 off the coast of Finistère.

Perimeter of the Parc Naturel Marin d’Iroise

Perimeter of the Parc Naturel Marin d’Iroise
Agence des aires marines protégées / SHOM

Focus of study

The topic studied was the ecosystem services provided by kelp forest habitats. The management of Laminaria hyperborea exploitation, the most abundant kelp species, has been implemented and negotiated 15 years ago by kelp harvesters. In a context of increasing demand for kelps, the main objective, through the ecosystem services assessment approach, was to provide new insights to the current management debate, and for the search of new trade-offs. The aim is to achieve precise management of the kelp field that allows a sustainable yield and employment for fishermen, while protecting patrimonial species as Bottle-nose dolphin and mitigating impacts on other uses.

A. Maulpoix / CNRS

Key stakeholders and their involvement

A dedicated commission of the Regional Fisheries Committee (CRPMEM) is in charge of defining proposals for kelp harvesting management rules, which are then amended and codified by the State representative.

Having some short-term objectives specified in the 2014-9271 regional regulation facilitated kelp harvesters’ involvement in many key steps of the ecosystem services assessment. Moreover, the Park’s council includes a wide range of local stakeholders. Through their debates, the team broadly analyzed the social demand of kelp ecosystem services and refined the kelp social-ecosystem representation.

Approach for Ecosystem Services Assessment

The triage of kelp ecosystem services was managed in order to reduce the scope of the assessment. Considering the numerous factors of influence which must be taken into account, the team chose to develop a dynamic model of the kelp social-ecosystem for simulating the impacts of various fisheries management options on 4 or 5 key ecosystem services.

The building of this model on a participative approach was the opportunity to identify available data and to make a precise assessment of gaps in data and knowledge. The model has sensitive metrics to drivers of change and provides indictors for the multi-criteria analysis of the scenarios impacts on ecosystem services.

Summary of main results

The stakeholder engagement and the workshops with scientists and managers provided a refined kelp social-ecosystem representation. The triage approach was necessary to select the most relevant ecosystem services. This was the basis upon a dynamic system simulation model was developed aiming at providing dynamically and quantitatively many indicators. At the end of the VALMER exercise, the model provided firsts numeric results and very preliminary simulations of scenarios.

Use of results

At this stage, the use of the dynamic model of kelp ecosystem services for comparing management options or simulating exploratory scenarios is only intended to help stakeholders and managers to better understand the global functioning of the whole system and to become used to include a wider range of parameters and indicators in their judgement over the kelp socio-ecosystem evolution. Using the model and the scenarios for operational management recommendations would be a step further.

Examples of lessons learned

Developing a dynamic system model provides a powerful tool to manage highly complex processes despite uncertainties and sometimes lack of knowledge. It is important to maintain the confidence and involvement of stakeholders during the process of construction of this tool. This semi-quantitative ecosystem services assessment is not a monetary valuation.

Faune du parc

Y. Turpin / AAMP

Photo: © F. Goulo / AAMP / PNMI | A. Maulpoix / CNRS