While there are only two types of pig farming, there are a dozen or more various labels that describe alternatively raised pork, known in the industry as "niche" pork. A 2006 Iowa State University report, "The United States Pork Niche Market Phenomenon" that the Times article quoted in an effort to estimate the number of pastured pigs in the US, lists the following niche pork attributes: "claim[s] [of] product differentiation by superior or unique product quality and social attributes. Quality attributes include certain swine breeds, and meat quality, freshness, taste or flavor, and tenderness. Social or credence attributes often are claimed and include freedom from antibiotics and growth promotants; local family farm production; natural, organic, outdoor, or bedded rearing; humane rearing; known origin; environmentally friendly production; and the absence of animal by-products in the feed."
In spite of the fact that there is no mention at all of pasture as a niche pork attribute in the pork niche market report, the Times article uses the report's estimate of the number of pigs raised in niche markets as an estimate of the number of pastured pigs raised in the US, 500,000 to 750,000 pigs. While according to the Times article "neither the United States Department of Agriculture nor the National Pork Producers Council has data on the number of pastured pigs," we do know that the number of pigs that are raised on pasture in the US is miniscule, which is why there are no statistics kept. In addition to the Iowa State report, Strom pointed out in her e-mailed response that the article also quotes Paul Willis, a pasture-based pig farmer, and the founder of the niche meat producer Niman Ranch's pork business, in an effort to round out the pastured pig estimate. From the article: "Paul Willis...estimated that as many as half of the pastured pigs raised today are in the Niman system." Extrapolating from the article, Niman Ranch slaughters about 150,000 pigs per year (3,000 per week). Therefore, per the Times' understanding, there would be approximately 300,000 pasture raised market pigs. However, the use of Paul Willis' quote illustrates further the depth of the confusion on the part of the Times. According to the Niman Ranch protocols (pdf), pigs can be raised on pasture or in "deep bedded pens." Deep bedded pens are a significant welfare improvement over the concrete slatted floors of industrial CAFOs. However, the welfare of pigs in well-managed deep bedded pens falls far short of the welfare of well-managed pigs on pasture. It is much more economical to raise pigs intensively than extensively, so the vast majority of Niman Ranch pigs are raised intensively in deep bedded pens; only a small percentage of Niman Ranch market pigs are raised on pasture. I attempted to contact Niman Ranch in an effort to get a firm estimate of that percentage, but I did not hear back from them.