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Concentrated Animal Feeding Operations (CAFOs)

Mary G. Henry1

Concentrated Animal Feeding Operations (CAFOs) are agricultural businesses where animals are grown under confined conditions, with many individuals crowded into one facility located on a few acres. Nationwide, the number of CAFOs has increased dramatically within the past several years. Although the number of producers has decreased, the number of animals per unit has increased. CAFOs commonly are clustered in one location or county.

CAFOs produce massive amounts of waste, including manure, urine, excess feed, and dead animals, which must be disposed of daily. This commonly is done by storing the waste in lagoons or holding facilities that frequently overflow as a result of exceeding the holding capacity or because of excessive rainfall. During these events, this untreated waste flows into nearby streams, wetlands, or watersheds. This waste also is spread on fields as fertilizer, which runs off into nearby waterways as nonpoint-source pollution.

Reduced water quality, through nutrient loading causing oxygen depletion and eutrophication, results in algal blooms and fish kills. Animal waste also has been linked to avian botulism and cholera, which are major threats to migratory birds. Other by-products of CAFOs include chemicals, ammonia and hydrogen sulfide gases, hormones, medicines, heavy metals, pesticides, and pathogens. These pollutants threaten the health and survival of wildlife, especially threatened and endangered species, and the land their existence relies on.

Changes need to occur to assure the continued health of our trust resources. More examples are needed to convince the farming industry and regulating agencies to support changes in the management, regulation, and enforcement of laws addressing CAFOs. In order to accomplish this change, we need to document the effects of CAFOs, distribute this information, and invite the industry to participate in creating the solutions. Only by forming partnerships and working as a team will a strategy be formed that all players can endorse and enforce.


1U.S. Fish and Wildlife Service, Branch of Ecosystems Health, 4401 North Fairfax Drive,
Suite 322, Arlington, VA 22203 (

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