Greenberg’s book brings up some valuable and useful questions about how—or if—we can sustainably harvest fish from their natural ecosystems or if we can instead manage this protein source via fish farms. Or if either are realistic. Throughout the book, I could feel my hopes rise as each fish from salmon, sea bass, cod, and tuna offered a possible solution; but then, my hope would fall as the solution seemed elusive. Toward the end of the book there is a hopeful example of ocean farming in the Pacific with the kahala—a species that meets many of the ideal characteristics of a farmable fish. Right now, it is working. But then I imagine them ramping up production to feed the world and I wonder if all the problems they are avoiding now with low demand disappear once it’s a global market? At the end of the day, the global population size is working against so many approaches.
One of the challenges of sustainably harvesting fish is that so many piscivores are removed from the ecosystem that the fish came from. I cannot see what is going on in Alaska where my salmon allegedly hails from—I do not know the fisherman who catch it or hear stories about what is happening in the habitat. I am removed from that system. So, should I be part of that food web? Should I instead be eating bluegill out of backyard ponds found all over Ohio? (Or, even better, just eating beans?) We travel to a sea faring destinations (or live there) and order the local fare, with some expectation that “someone” is monitoring the situation and making decisions that allow for safe, sustainable harvest. However, the tuna serves an example that this is not the case—that science isn’t guiding the management of this high trophic-level fish, but rather demand and the fishing industry is.
Can you remove a food source from any natural system, send it around the world, and expect to do so sustainably in a world with 7.5 billion people? It seems unlikely. The most telling story in the book to me was that of the moratorium on whale hunting that resulted from the International Whaling Commission. While the intention may have been to reduce hunting pressure to allow populations to rebound, there was also a shift in perception about whale hunting and a shift in need for whale products. The ban continues, despite some country’s violation (in spirit if not always law), and the populations recover. For Bluefin tuna, the solution may be the same, but such solutions are resisted.
The key to the problem, Greenberg suggests, is public perception. It worked with swordfish: “Give Swordfish a Break.” By (mainly) convincing chefs not to serve swordfish, it reduced demand and swordfish populations recovered. Many environmentally conscience people are carrying around “Seafood Watch” cards and trying to make good decisions on their menu selections, but as Greenberg points out: There has been no clear benefit to fish populations. (I have ruined many a dinner with my husband’s family by whipping out my card, which no doubt has improved my popularity.) So public perception may need to move in the direction of reduced demand for fish.
Overall, this book highlights the complications of a world with so many hungry people. Although he offers solutions at the end, it all boils down to less is more.