How is Wild Planets offering of smaller, juvenile tuna with less mercury consistent with a sustainability mission when these young fish have not had a chance to breed?
There are two fishery segments targeting albacore tuna worldwide: 1) surface fisheries catching migratory juveniles and 2) deep water long-line fisheries capturing spawning stocks. It is counter intuitive to assume that the most sustainable method of catch is to shift effort to juveniles since they have never bred. However, if all fish should be allowed to breed before harvest then there would be no commercial salmon industry since all commercial salmon have also not bred. The salmon stocks are managed by assessment of percentage of capture versus escapement. If an adequate percentage escape capture to go on to reproduce, then the fishery is considered sustainable. In the albacore world, the surface fisheries are artisanal methods of harvest that are fairly ineffective in capture compared to long-line fisheries. The West Coast troll and pole fishery captures less than 15% of the bio-mass resulting in 85% of the fish returning to the spawning stocks. This 85% escapement is sufficient to
