PROJECT DESCRIPTION
BACKGROUND
The expansion in the Mediterranea of the green alga Caulerpa taxifolia has progressed steadily since 1984. This plant represents a serious danger in the biodiversity of the sea, and in particular to one of the most characteristic and important of the Mediterranean ecosystem, the Posidonia oceanica meadows, which enjoys legal protection in Spain (Catalonia, Valencia) and France, and is included in Appendix 1 of the Habitats Directive. (1) An essential requirement for the development of a prosper strategy to control its expansion (point 2) is to ensure the rapid detection of new stations, in particular in areas that are distant from the Eze-Menton (Alpes-Maritimes, France) area, that is already heavily colonized. This requires that efforts to alert the public to the problem should continue. Documents will be published or re-published in English, French, Catalan and Spanish, and the public awareness campaign will be extended to the countries on the southern shores of the Mediterranea (Malta, Tunisia and Algeria) thare are likely to be concerned by the spread of C. taxifolia. A predictive model of the species' expansion will be developed for the purpose of identifying the areas and biotopes at risk, where there is high probability of finding new stations of Caulerpa taxifolia. The new stations that are discovered through the help of the public or through systematic exploration of the sensitive areas or biotopes will be mapped in order to provide a basis for deciding on the appropriate expansion control strategy. (2) The improvement of eradication will focus on three techniques: (i) using hot oversalting, (ii) copper ions, by electrolytic procedures, and (iii) copper ions, by an ion-exchanging membrane. Every effort will be made to reduce the costs, to improve the efficiency (which will be compared with that of manual eradication) and to minimise the environmental impact. In particular, we will attempt to replace the copper with a biodegradable algicide. An expansion control strategy will then be proposed to the decision-makers, that will take into account the predictive expansion model, the localisation and characteristics of the news stations and the most appropriate eradictation technique (or set of techniques). (3) Knowledge of the possible impact of the expansion of Caulerpa taxifolia on commercially exploited species will be a major factor to be taken into account for deciding on an expansion control strategy. In particular, we will attempt to identify the degradation products of caulerpenyne, and to trace their possible accumulation through the food chains. (4) There would be no point in controlling the expansion of Caulerpa taxifolia along northern coasts of the Mediteranea, if the southern coasts are neglected. The arrival Caulerpa taxifolia in Sicily has increased the risk of its spreading to Malta, Tunisia or Algeria. It is therefore essential to alert the public and the decision-makers to this danger, and to train scientists to recognise and subsequently eradicate the species. This training in recognition will be carried out in the form of seminars that will be organised in the southern Mediterranean countries (except Algeria). Training in eradication will be ensured by including staff from the southern mediterranean countries in the teams responsible for testing eradication techniques in the northern Mediterranean countries.