In reviewing the comments provided by Dr. Bell, I am encouraged that the conclusions of the recent work of my colleagues and I are already promoting discussion within the field and I sincerely appreciate his feedback and additional thoughtful perspective.
The innate challenge of doing global research is that while important large-scale trends are observed, regional or micro-trends may be obscured—such as capturing implications for food insecure individuals within a country that is considered food secure at the national level. While my co-authors and I touched on this issue and a couple others, we were limited in our ability to fully assess all potential circumstances pertaining to the consumption of species included in our analyses. There are no data that I can present here that are not already contained in our paper. That said, I am quite familiar with the extensive research that Dr. Bell has led and co-authored regarding Pacific Island fisheries and food security and, as a result, this region was at the forefront of my mind when I began the analyses (as were other island states such as the Maldives).
Based on the results in our paper, none of Pacific Island countries and territories are high seas fishing nations or primary importers of high seas fish. Similarly, while the Maldives has one of the highest seafood consumption rates in the world—around 200 kg per capita annually—the majority of tuna consumed there is fresh tuna caught by their domestic pole-and-line skipjack fishery. That said, I cannot refute the notion that some canned tuna consumed in low-income island states (or other low-income countries) may have been caught by high seas fisheries. And, independent of that volume, for people who depend on this type of protein to meet their food security needs, it is essential if no alternatives are available. However, Dr. Bell’s estimate that upward of 60% of canned tuna consumed in some Pacific Island nations is imported is concerning given that tuna is the primary natural resource available within most of these EEZs. To this end, it appears that access to Pacific tuna stocks is currently inequitable and adds support to the conclusion that high seas fisheries are dominated by a few fleets.
Second, while we did mention potential changes in stock structure for certain tuna species under climate change, it was beyond the scope of this paper to delve into the implications of these future projections. That said, since it was mentioned by Dr. Bell, I would like to add that it is important to differentiate between changes in fishing effort due mostly to ecological conditions versus changes in the distribution of fisheries that also result from prevailing socio-economic conditions. In the next few decades, biomass of skipjack and yellowfin is anticipated to shift eastward to Pacific Island EEZs that are currently subject to lower fishing effort for tuna. While substantial uncertainties around population dynamics remain, additional political uncertainties (e.g. rearrangements of fishing access agreements) will also affect how and where these stocks are exploited in the future and who will benefit from these fisheries.
To this end, discussions around the management of the high seas—and any marine space—need to integrate both ecological and social factors. And, with regard to the latter, they must ensure that the burden of conservation measures is equitably distributed across states. All global analyses and model projections have limitations so waiting for perfect information should not be a reason to forgo our current understanding of a system, or a reason to avoid precautionary fisheries management if there are uncertainties. If a spatial management component would assist in ensuring the long-term conservation of high seas biodiversity through a UN treaty, then that is something that should remain on the table. That said, the multitude of information that must feed into this decision extends well beyond the results of a single paper or model—only when considered comprehensively can independent research contributions inform policy. With regard to our study, I stand by the original conclusions and am confident that this work provides valuable insight into one aspect of this discussion.
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