Does anyone on the forum know much about international fishing regulations? I learned recently that there is high demand for Atlantic bluefin tuna (Thunnus thynnus) in East Asian markets, despite the fact that they are listed as an IUCN endangered species. It makes little sense to me that there would be a market for this fish in East Asia considering there are several Thunnus species available in the Pacific that are not endangered and don’t require the exorbitant shipping cost to get them from the Atlantic to the Pacific while they’re still fresh. Does the demand pose a significant threat to the species? Do harvesting regulations do anything to curb demand? Are regulations just too weak to make a difference? Is enforcement too lax?
On a related note, what species of tuna are most commonly sold at East Asian fish markets? Fish merchants in East Asia make a show out of cutting the big tuna for sashimi, which I don’t have any objection to–It can be fascinating to watch (e.g. this video from the Noryangjin fish market in Seoul [Fair warning: the video depicts a typical tuna butchering demonstration. If that sounds too graphic for you, refrain from watching]. Can anyone identify the species in the video?)–but I would be very upset to see an endangered species butchered.
For an education on Atlantic tuna regulations, see this site: https://www.iccat.int (probably more detail than you’re looking for).
I’m not an expert on tuna, but did, as part of my former job, review some of the US Atlantic Bluefin regulations. The fundamental problem with regulation for all tunas is that they are highly migratory (meaning they move across national jurisdictions), and are often fished on the high seas (outside of national waters). Regulation is by international agreement, and for the most part the agreed regulations are fairly conservation-oriented. However, not all countries sign onto the agreements, not all that do sign on have the resources to enforce regulations, and given the extremely high market value of tuna, rogue fishers can afford technology (fast ships and electronics) to avoid enforcement.
Spot on, those are the core issues. Pohnpei, where I live and work, is home to the Western and Central Pacific Fisheries Commission which works to bring together distant water consumer nations with Pacific producing nations to form agreements on fisheries stock management. The largest remaining industrial scale stocks of tuna remain in the Pacific. Skipjack tuna is said to be the most abundant stock and appears to remain at sustainable levels. Bluefin is apparently not found in these warmer waters, not as far as I am aware. Yellow fin is the choice for sashimi grade export. Bigeye stocks are thought to potentially be problematic. Albacore is apparently a southern hemisphere species not seen up here.
These appear to be smallish bluefin tuna, probably Pacific ( Thunnus orientalis), although it’s been a long time since I had anything to do with these fisheries. The price commanded by top quality bluefin tuna more than makes up for the cost of air freight.
I was a member of the Inter-American Tropical Tuna Commission’s Scientific Committee for a little while and I feel confidant in saying that the scientific advice being provided by the IATTC staff was pretty straight up and credible, albeit with lots of room for argument about method and interpretation. I expect that ICCAT is much the same. As @twainwright notes, the main issues relate to the migratory nature of tunas and the breathtaking prices the most desirable species (the bluefins) fetch at auction in Japan. Yes there are other tuna species and there are large fisheries on them but the highest value is in bluefins. The regulatory system is subject to brokerage politics and illegal, unreported and unregulated fisheries on the high seas make for a very uneven playing field for those involved in the industry with potential for big rewards and relatively little risk of penalties for rule-breaking.
Thanks for the input all. Fisheries and fishing regs are pretty far outside of my area of expertise, but I’d still like to be a little more aware of what is happening in the world with endangered marine species. I wish I had a little more time to devote to researching.