Firth, L. B., Thompson, R. C., Bohn, K., Abbiati, M., Airoldi, L., Bouma, T. J., Bozzeda, F., Ceccherelli, V. U., Colangelo, M. A., Evans, A., Ferrario, F., Hanely, M. E., Hinz, H., Hoggart, S. P. G., Jackson, J. E., Moore, P., Morgan, E. H., Perkol-Finkel, S., Skov, M. W., Strain, E. M., van Belzen, J., Hawkins, S. J. (2014). Between a rock and a hard place: Environmental and engineering considerations when designing coastal defence structures. Coastal Engineering, 87, 122-135Coastal defence structures are proliferating as a result of rising sea levels and stormier seas. With the realisation that most coastal infrastructure cannot be lost or removed, research is required into ways that coastal defence structures can be built to meet engineering requirements, whilst also providing relevant ecosystem services so-called ecological engineering. This approach requires an understanding of the types of assemblages and their functional roles that are desirable and feasible in these novel ecosystems. We review the major impacts coastal defence structures have on surrounding environments and recent experiments informing building coastal defences in a more ecologically sustainable manner. We summarise research carried out during the THESEUS project (2009-2014) which optimised the design of coastal defence structures with the aim to conserve or restore native species diversity. Native biodiversity could be manipulated on defence structures through various interventions: we created artificial rock pools, pits and crevices on breakwaters; we deployed a precast habitat enhancement unit in a coastal defence scheme; we tested the use of a mixture of stone sizes in gabion baskets; and we gardened native habitat-forming species, such as threatened canopy-forming algae on coastal defence structures. Finally, we outline guidelines and recommendations to provide multiple ecosystem services while maintaining engineering efficacy. This work demonstrated that simple enhancement methods can be cost-effective measures to manage local biodiversity. Care is required, however, in the wholesale implementation of these recommendations without full consideration of the desired effects and overall management goals. (C) 2013 Elsevier B.V. All rights reserved.authorsversionPeer reviewe

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In this study, we describe what we term a Blue Transition, defined as the passage from fish biomass reduction to recovery in exploited aquatic resources, enabled by aquaculture. A Blue Transition is a key component of emergent “blue” discourses which support that the expansion of aquaculture would relieve pressure on declining capture fisheries, thus contributing to global food security, particularly of the poorest populations. Based on global secondary data and the case of Chile, we explore the evidence of such claim and the implications of a Blue Transition for fisheries and aquaculture development. In 2012, worldwide aquaculture production surpassed wild captures; nevertheless, such turnaround would have not taken place without China's contribution. In Chile, this turnaround occurred in 2014, concurrently with the lowest industrial landings registered since the 1960s (1,227,359 tons). Chile's aquaculture is not relieving wild fisheries or satisfying food demands of the lower income population, in the country or elsewhere. Salmon, the main aquaculture product, is destined mainly to Japan, Russia and United States where, due to its high prices, it is consumed mostly by wealthy consumers. For the case at hand, evidence suggests that a blue transition may be underway but is going in the wrong direction: from what may have been sustainable fisheries management before the 1970s to the overexploited wild fisheries of today.