It should also be noted that to effectively implement controls on the total number

Forskolin supplier of FADs fished on or deployed it would be necessary to ensure compliance with effort limits using measures such as closed circuit television or on-board observers. In the past two decades the use of FADs has reshaped the dynamics of purse seine fleets, particularly in the Indian Ocean. The improved catch levels made possible by this fishing practice facilitated a rapid growth of the fishery, and the subsequent development of the fleet, in particular the Spanish component, has largely been based around the use of FADs. Thus, with the use of FADs being increasingly vital to the fishing operations of many vessels, their use is not expected to decline under a business-as-usual scenario, potentially rekindling the excess capacity observed in

the fishery in the past [36]. However, any increase in the use of FADs would not necessarily mean a uniform increase in fishing effort throughout the western Indian Ocean, but rather increased intensity of effort in the main FAD fishing regions. The fishery and ecological effects of such a change in the spatial dynamics of effort are not well understood, although recent modelling work suggests that an increase in the number of FADs in a region would probably signaling pathway result in smaller schools distributed between greater number of objects. Thus search costs and bycatch might increase, rather than catches [44]. A number of external pressures might also be expected to change the face of FAD fishing in the future, although conflicting pressures have the potential to push the industry in different directions. Purse seine fishing has become an increasingly expensive operation over the past decade, particularly for the largest and most powerful vessels, due to rising fuel prices and increased fishing effort [3]. This has reduced profit margins and potentially increased the fisheries’ economic vulnerability to poor fishing seasons Glycogen branching enzyme and environmental or economic shocks. Given

the past trends it might be reasonable to assume that this situation would provoke an even stronger reliance on FADs, especially for those vessels that still target a relatively large proportion of free schools. Again, this might result in the saturation of the FAD fishery, potentially leading to increased costs, lower catches but high total extraction rates. In contrast, market pressures might result in reduced effort on FADs. The majority of the skipjack caught in the Indian Ocean purse seine fishery is of canning grade and destined for markets in the European Community countries [32]. Here consumer pressure for sustainably sourced fish is strong and seafood certification schemes, such as that of the Marine Stewardship Council (MSC), are popular [45].