|Certainly chickens fed on waste and kept on arable land would be an ideal form of self-generating protein, but I don't think that reflects the reality of free range poultry farms, although I may be wrong about that.|
Iím currently in the middle of Michael Pollanís The Omnivoreís Dilemma which has a lot to say on this very subject.
Though he doesnít make a direct comparison of free range farming and battery farming, Pollan does note that, in order to operate on a larger scale, ethical farming methods increasingly incorporate industrial practices to remain competitive, and that accordingly (in a section where heís indirectly quite scathing about the reality of portions of the American ethical food industry) thereís significantly less difference environmentally between (for example) organic and non-organic methodology than one might have hoped for. To qualify for free range status might mean slightly larger cages, or hens which a limited period of access to the outside from where theyíre held, rather than the more benign pastoral image of them roaming around freely, to qualify for ďorganicĒ status might mean the restriction but not elimination of synthetic elements.
At several points he mentions Whole Foods Ė which I believe is primarily a large chain of expensive American ethical/organic supermarkets Ė any U.S. Ďlithers want to confirm what itís like shopping there? The point being, that to exist as a national chain thereís a need for national distribution which offsets a great deal of the original environmental benefits to the products, and that appears to be a much greater environmental benefit to local and seasonal, as opposed to say organic, produce. I imagine that thereís at least to some degree a similar story with somewhere like Tesco.
One of Pollanís counter-examples to the above, rotational farming, has exactly whatís described above, chickens being kept whose excrement is used as fertiliser for pastures in which livestock grazes, and who in turn help to keep the livestock healthy by picking parasites out of the livestock's droppings. Even in the reductive summary Iím giving you: better for the chickens, better for the livestock, better for the land, better for the consumer. There are so many variables as to determine whether itís overall better for the environment as a whole that Iíd struggle to offer a conclusion, certainly the impression I got was that itís sustainable, in that the land doesnít need to be supplemented by lots of fertiliser, more efficient in that the animals donít need as intensive a programme of antibiotics to keep them healthy/tasty, and more economical in that the consumers are potentially passing on the benefits of eating healthier food by being, well, healthier. The fact that this type of farming is labour-intensive, small scale and localised would be the most obvious disadvantages to why its produce is not more popularly available.
Another factor that Iím interested in is how these different methods of farming effect the movement of information: the rotational farming above is all about knowing exactly where your food comes from, organic farming uses that but idea not always perfectly, industrial farming is invested in there being as little movement of information as possible. That said, some people will not want to know that their eggs taste so good because the chickens that hatched them had access to the juicy grubs found in cowshit.
Also, what still hasn't been addressed is the relative numbers of people fed via each farming method or other, alternative, uses of the land.
Iíve a feeling that to answer that weíre going to start moving away from inquiring into the limits of oneís personal stance and into the sustainability of ethical farming at a national or global level. Would there be interest in a new thread on economics / agriculture in the Switchboard or Lab?