FADs for marine conservation?

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By Elizabeth M. De Santo, Ph.D., Assistant Professor of Environmental Studies, Franklin & Marshall College

In a recent Nature News piece, Daniel Cressey discusses the sustainability concerns posed by fish aggregating devices (FADs), drawing on the work of Davies et al., who examined FADs in the Indian Ocean. This is an interesting phenomenon – fishermen increase their catches by floating rafts or other structures that attract fish (and signal their location via radio transmitters), which works because fish are naturally attracted to and congregate under these sheltering structures. However, FADs are poorly regulated, add to overfishing, and their impacts on ecosystems are unknown.

The Nature piece also cites the work Cabral et al., whose research on tuna indicates that FADs increase catch per boat when total fishing pressure is low, but can result in fishery collapse when fishing effort is high. The authors suggest that FADs deployed in no-fishing areas (which they refer to as fish enhancing devices, or FEDs) are gaining popularity as a fisheries management tool in the western Pacific.

This raises a provocative question for those of us working in the field of MPAs and selling their benefits to the fishing community. Should we deploy FEDs in no-take areas as part of MPA planning? Would such devices increase spillover effects or hamper them? Would the fishing community resent conservationists using their tools "against them"? What do others think, based on your experiences and insights in the field? Please comment!


One of the main challenges of no-take MPAs for fishery recovery objectives is that wide-ranging pelagic fish 'stocks' will not be conferred protective benefits by such site-specific designations. FADs could contribute to addressing this challenge by encouraging some fish to remain within the MPA rather than simply swimming across it, only to be caught on the way in or the way out or in the wider sea. Some pelagic fish would still swim out having stayed in the MPA long enough to get bigger, conferring spillover benefits, but maybe enough would stay in the MPA long enough to become BOFFFFs and confer propagule export benefits? As with all such proposals, why not pilot this approach, study the responses and evaluate them. If it works, use FADs in MPAs, if it does not, at least we know. We certainly should not dismiss the idea because of ethical worries about using a fisheries exploitation method to try and protect fisheries. Nor are we turning a fisheries exploitation method against the fishermen, as they would still gain wider spillover and export benefits from pelagic fish populations that learn to hang out around FADs within MPAs. We should experiment with the use of FADs in MPAs rather than dismissing this approach on idealogical grounds or 'turning their weapons against them' worries.

I think the issue of whether or not to deploy FADs should also recognise their consequences in terms of access rights, ownership and equity. FADs will benefit those with the equipment to access pelagic fisheries, which may not necessarily reduce pressure on reef fisheries if the fishery is characterised by small boats with limited technology. Furthermore, the economic benefits are therefore concentrated in the hands of the local 'elite' which does not assist in the general fishers' perception of fisheries management interventions. My experience in Indonesia also highlighted the consequences of disputed ownership of FADs, which eventually resulted in a powerful minority deciding to allow commercial purse seining around the FADs as they believed they had the rights to exploit fish around the FADs owing to their contribution towards their construction. Needless to say, the fish congregations around the FADs were immediately depleted. Whether or not FADs contribute towards spillover I'm not sure, but their presence can lead to a myriad of complex and often counter-productive issues within the fishery.

I completely agree with Julian's points about the equity and access issues that FADs can raise, but if FADs were deployed in MPAs with the intention that they were not to be fished around, the aim being to increase the retention of pelagic fish within the MPA, would these equity issues apply? There may, though, be equity issues if the FADs in MPAs initially reduce surrounding catches outside but in the vicinity of the MPA, at least until (when or if?) the spillover and export benfits start to flow? Incidentally, a recent paper* on the site fidelity of Yellowfin Tuna in an MPA in Mexico indicates that MPAs can contribute to the conservation of pelagic stocks, which display more site fidelity than was previously thought. If FADs increase this site fidelity, that could increase the potential of MPAs to contribute to sustainable pelagic fisheries? * Schaefer et al (2014) Movements, behavior, and habitat utilization of yellowfin tuna (Thunnus albacares) in waters surrounding the Revillagigedo Islands Archipelago Biosphere Reserve, Mexico. Fish. Oceanogr. 23:1, 65–82, doi:10.1111/fog.12047

MPA FADs could for some folks be rather tempting, one-stop shopping.. (Get all the BOFFFs here!) So, ethics and equity aside outside of the MPA, in order for FADS not to become a perverse incentive to illegally fish within an MPA, they would have to be equipped with surveillance equipment. This need not be fancy, say a hydrophone and satellite telephone transmitter, but would add to the cost, and would demand that enforcement personnel could respond quickly. Otherwise, not only would the big fish fish be gone, but perhaps the sat phone as well... Managing MPAs would be easy, if it weren't for the humans!

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