Cyanide Hazards Birds

To protect wildlife, various techniques were used including cyanide recovery, cyanide destmction, physical barriers, hazing, and establishment of decoy ponds. Techniques that were 92% successful (i.e., 8% mortality) cost mine owners about 8.58 per dead bird This 92% survival was considered unsatisfactory by the U.S. Bureau of Land Management, and 

Free cyanide levels associated with high avian death rates have included 0.12mg/L in air, 2.1-4.6mg/kg body weight (BW) via acute oral exposure, and 1.3mg/kg BW administered intravenously. In cyanide-tolerant species, such as the domestic chicken (G alius dome Stic us), dietary levels of 135.0 mg total CN/kg ration resulted in growth reduction 

Some birds may not die immediately after drinking lethal cyanide solutions. Sodium cyanide rapidly forms free cyanide in the avian digestive tract (pH 1.3-6.5), whereas formation of free cyanide from metal cyanide complexes is comparatively slow. A high rate of 

Under the Migratory Bird Treaty Act, cyanide-containing ponds must be maintained 

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