Block is emphatic that it is not too late to save the western stock. "We have evidence in the genome that we're looking at that there's still a lot of genetic variation, even though the fish are very depleted," she said.
"Our North Atlantic fishery is composed of two populations: a Mediterranean-spawned bluefin and a fish from the smaller Gulf of Mexico spawning ground that are virtually impossible to identify without a genetic approach or a tag track that spans years," Block said.
"I believe that stock identification techniques, including genetics and elemental analyses of the ear bone, will be in place within the year to more accurately determine the percentage of fish from each population," she said. "We have the scientific tools to determine exactly how many of the eastern fish are boosting our fishery, and we can determine how many of the Gulf of Mexico stock are left."
Block and her team are collaborating with mathematicians who build stock assessment models at the University of British Columbia to generate a more accurate fisheries-assessment model that includes the detailed spatial information incorporated from the tagging data as well as the genetic origin of the tagged fish.
Block said saving the Gulf of Mexico population of bluefin will require everyone to pitch in. "We cannot do it alone. We need international fishers to recognize that they must stop catching our giants on the foraging grounds in the middle of the Atlantic," she said. "And here at home, we have to stop the bycatch in our own backyard." Block thinks high-tech solutions involving vessel and fish monitoring via satellite may be the only way to monitor the high seas.
"If we really want to ensure that our children see giant bluefin, we have to stop killing
western giants before they're ma
|Contact: Louis Bergeron|