The growing popularity of marine recreational fishing has created considerable interest in artificial marine habitat development to maintain and enhance coastal fishery stocks. This paper provides a comparative evaluation of travel cost methods to estimate recreational use benefits for new habitat site planning. Theoretical concerns about price and quality effects of substitute sites, corner solutions in site choice, and econometric estimation are considered. Results from a case study indicate that benefit estimates are influenced by the way these concerns are addressed, but relatively simple single site models can provide defensible estimates. Practical limitations on data collection and model estimation are also considered.

Understanding the role played by sunken vessels in Mediterranean marine ecosystems is acquiring increasing importance. The aim of this research was to study the fish communities associated with four shipwrecks, by means of underwater visual censuses performed by a remotely operated vehicle, and to test the differences in composition of fish assemblages between these shipwrecks and the adjacent soft bottoms, considered as control sites. Multivariate analysis on the total fish assemblage showed significant differences between wrecks and controls. Results also showed higher levels of species richness and abundance near all wrecks than at a short distance from them on soft bottoms, thus indicating that these sunken vessels, thanks to their higher habitat complexity, act as artificial reefs, attracting aggregations of fish species and leading to a greater diversification of the local fish assemblage. Nevertheless, shipwrecks, which are an ideal target for recreational fishermen, could contribute to the over-exploitation of some high-value fish species, such as Mycteroperca rubra, Dentex dentex and Diplodus spp., attracted by the artificial hard substrate of the vessel-reefs. The recent European directives suggest an urgent need for a better understanding of the crucial role played by these potential sources of pollutants on marine environments and ecosystems. An ecosystem approach to study and monitor these pollutant sources is, therefore, mandatory for appropriate remediation and/or mitigation of the potential negative effects on a productive and healthy ocean.

The pressures on the use of the seashore are steadily rising, not only in developed countries but worldwide. Anthropogenic activity has long impacted the marine continental shelf down to a depth of approximately –200 m. New activities are now affecting this coastal space such as renewable energies, recreational uses and aquaculture in addition to the traditional ones of navigation or fishing. This evolution raises new sources of conflict amongst users which can require state involvement in order to manage the different stakeholders and pressure groups. However, the coastal space still offers a large potential for development for two reasons. Firstly, the physical three dimensional potential of this space enables the whole water column to be used, principally to increase the fishing productivity as in Japan. Secondly, innovative synergies can be created between socio-technical and ecological uses (a “fourth dimension”) such as the eco-design of wind turbine foundations in order to create fish habitat or sea grass settlement. This new vision in “4D” for the design and the management of coastal infrastructure can potentially reduce the risk of conflict as different uses of the coastal space would not necessarily exclude one another. Indeed, several forms of synergy could be developed such as fisheries with aquaculture or biological sustainability with social acceptability. Until now, limited attempts at such an approach have been done. We suggest this is likely due to the absence of a common eco-engineering vision and the lack of experience amongst biologists and engineers in the co-construction of projects. This eco-engineering, or “green” vision, also takes into account the complexity and resilience of the ecosystem in the long term, if underwater engineered infrastructures are also “eco”-designed to increase ecological gain This new conception, for development within the coastal area, provides for an increased bio-oriented complexity to engineered structure and therefore a better resistance of the ecosystem in the long term to anthropogenic pressures and a reduction in multi-user conflicts.