supply domestic markets has increased in countries such as Italy, France, Germany, Denmark, and Spain. Other significant trout-producing countries include the U.S., Iran, the United Kingdom, and Lesotho. While the U.S. rainbow trout industry as a whole is viewed as ecologically responsible, trout raised elsewhere are not necessarily farmed with the same methods. About three-quarters of U.S. production comes from Idaho, particularly the Snake River area, due in part to the quality and temperature of the water available there. California and Washington also produce significant numbers of farmed trout. In the east, Pennsylvania, North Carolina and West Virginia have farming operations. Rainbow trout farming is one of the largest finfish aquaculture industries in the U.S. They are raised inland in facilities where raceways or ponds have continuously flowing water with little pollution and a low risk of escape. The U.S. industry is noted for using best management practices. Imports constitute only about 15 percent of farmed rainbows sold in the U.S., and nearly all domestic production is consumed within the country; very little is exported. The U.S. produces about 7 percent of the world's farmed trout. Rainbow trout, especially those raised in farms and hatcheries, are susceptible to enteric redmouth disease. A considerable amount of research has been conducted on redmouth disease, given its serious implications for rainbow trout farming. The disease does not infect humans. There have been recent interest and efforts in introducing a rainbow trout species that can be completely fed on a vegan diet through genetic selection. Research from a study team led by USDA research geneticist Dr. Ken Overturf concluded that such natural genetic variation of vegan trouts does exist and believe they can produce rainbow trouts that can be completely fed on a 100% plant-based diet. Conservation Populations of many rainbow trout subspecies, including anadromous forms (steelhead) of (coastal rainbow trout) and (Columbia River redband trout), have declined in their native ranges due to over-harvest, habitat loss, disease, invasive species, pollution and hybridization with other subspecies, and some introduced populations, once healthy, have declined for the same reasons. As a consequence, some rainbow populations, particularly anadromous forms within their native range, have been classified as endangered, threatened or species of special concern by federal or state agencies. Rainbow trout, and subspecies thereof, are currently a U.S. Environmental Protection Agency-approved indicator species for acute freshwater toxicity testing. Many non-profit organizations have formed to protect, conserve