Discussing the Merits of Aquaculture
by Jeremy Elton Jacquot, Los Angeles on 06.19.07
Jeffrey Sachs, the director of the Earth Institute at Columbia University and world-renowned anti-poverty crusader, has turned his prodigious attention to an issue dear to many of us in the TreeHugger community: environmental sustainability. Citing figures that project the world's population to reach a staggering nine billion by 2050, with an average output of $20,000 or more, Sachs argues that new technologies are needed to raise living standards while also softening the human impact on the environment
That silver bullet: aquaculture, which he claims could support rising consumption of seafood while reducing anthropogenic pressures on oceanic ecosystems. This "Blue Revolution" has come at a critical time because, as he put it:
"Between 1950 and today the total landed catch from open- and inland-sea fishing almost quintupled, from around 20 million to about 95 million metric tons. Both higher demand from rising world incomes and higher supply from more powerful fishing vessels contributed to the surge. So, too, did large and misguided subsidies to fishing fleets, reflecting the political power of geographically concentrated fishing communities and industries. The world put itself on a course to gut ocean ecosystems, with devastating consequences."
It is certainly the case that aquaculture has come a long way since the early 1950s when it first became widely used. Yields have surged from around 2 million metric tons in 1950 to 50 million metric tons today, and recent studies have shown a marked improvement in its efficiency and an increase in the range of species that can be domesticated (106 out of the more than 400 farmed species).
Yet aquaculture is not without its faults, a fact that Sachs readily admits; nor is it the only solution to the problems facing our oceans. The main concern is, of course, the massive scale of habitat destruction wreaked by the displacement or cutting down of coastal ecosystems to create new areas for farming (particularly for shrimp). The significant amounts of catch needed to feed the farmed organisms and the release of excess nutrients and antibiotics, which can lead to eutrophication, also act to further exert tremendous pressure on the oceans.
Nevertheless, Sachs is encouraged by signs of rapid improvement in the current aquaculture technologies and believes that, with the right incentives (i.e. prizes or funding), further research could be done to continually polish them. It goes without saying that we wholeheartedly agree with his arguments that subsidies for unsustainable fishing should be eliminated and that devastating practices such as bottom trawling on seamounts should be outlawed.
People often forget that the oceans account for close to 70% of the planet's surface. It's about time we find viable, long-term solutions to utilizing their resources. A more environmentally friendly form of aquaculture, in addition to more sustainable fishing practices, is a step in the right direction.
Via ::The Promise of the Blue Revolution (magazine)
See also: ::You and Me, ::Happy Shrimp Goes Local in Rotterdam, ::New Zealand Bans Bottom-Trawling, but..., ::The TH Interview: Mark Powell, Vice President in Charge of Fish Conservation at The Ocean Conservancy
Another issue with aquaculture is the potential for escape by the farmed species, which are often an exotic, invasive alien species that may decimate native species or interbreed, and otherwise cause the decline of native species, such as through the spread of disease.
Oceans are indeed large, but aquaculture generally needs to occur in relatively calm waters so that pens or enclosures aren't destroyed, and agacency to the coast or ports is helpful for servicing and harvesting needs.
E O Wilson points out that by his calculations, humans already use more than half of the earth's annual biological production - from all sources, including aquatic. By intercepting and removing this production from the ecosystem we have introduced enormous instabilities and are effectively starving other species.
I would hope that there are other models for aquaculture other than those currently being used. If we could build up fisheries stocks to the point they were at before the introduction of industrialized fishing fleets we might realize tremendous improvements in the overall health of fisheries, and benefit the ecosystem.
Adults simply do NOT need the all animal protein they consume. Although essential for kids, after the age of 25, your need for animal protein drops dramatically. In fact, excess animal protein may promote growth factors that kick cancers into overdrive. We need to worry about farming more nutritious plant matter for end consumption by humans, rather than using our farms to grow animal and fish feed. All of us Treehuggers have known THAT since Diet for a Small Planet.
Then of course there's the fishmeal issue. As long as the growth in aquaculture is for vegetarian fish like catfish, tilapia, carp and milkfish, it's fine. We'll never be able to farm tuna sustainably because they need to eat fish to survive, and it wouldn't make economic sense to farm fish to feed the tunas. It would be like trying to grow tigers for meat. If we want to turn solely to aquaculture, we're going to have to ask people to eat lower on the food chain (like chickens (mostly vegetarian-they need to eat bugs to survive), cows (all vegetarian) or sheep (all vegetarian)).
We could "just say no" to aquaculture, but where would that get us? As this article correctly points out, we need to find viable, long-term solutions for using fish and shellfish to feed people. Aquaculture done right can be part of the solution.
There's much to be done in learning to do aquaculture right. We need to commit to an aquaculture industry in tune with natural processes, not fighting against them. We should focus on herbivorous fish and shellfish, use sustainable feed, and find technologies that minimize pollution, disease and escape problems.
Tough, but we have no other choice. "Just say no" is not a viable option.
A key point that needs to be made is that aquaculture is very expensive and technology dependant. It requires a high level of infrastructure and expertise to operate successfully. Commercially run aquaculture operations are generally high risk and involve a large capital to set up. I'm not sure that aquaculture is an appropriate solution for developing world poverty and hunger.
It may however allow us in the more affluent countries to continue to enjoy such luxuries as throwing a shrimp on the barbie, or searing a salmon steak. ;)
I think you all raise some excellent questions. As jon mentions, several important factors need to be taken into consideration when setting up the farms (not least of which is the fact that a farmed species could become invasive in the right ecosystem). While aquaculture technologies in their current form are fairly wasteful and expensive, prices will most likely begin to rapidly drop as they improve and become more sustainable, something that will help make them available to less developed countries. As Mark notes, simply saying "no" to aquaculture is NOT the solution.