The California Department of Fish and Game has been investigating four major aspects of waterfowl lead poisoning. Randomly selected soil samples taken from four locations were examined to determine availability of lead pellets. These have shown a range of 0-188 pellets per plot for one hundred twenty, one meter square by ten centimeter deep, plots. To determine levels of ingested lead shot, gizzards were taken from trapped, hunter and disease killed birds. Of 3,799 gizzards examined, 294 (7.74%) contained ingested lead pellets. Wingbone and tissue samples chemically analyzed for lead content have been of no help in differentiating sources of lead in waterfowl. In wingbone samples of seemingly alike immature ducks, values ranged from <1-871 ppm per sample. Actual confirmed mortality? for the last two years has been approximately 150 waterfowl. Estimated mortality statewide has been 2,000.
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