Cartridge Company, which is a Division of the Olin Industries, Inc., and the University of Illinois. In the 
course of the investigation, many other agencies and individuals have given assistance. 
The purposes of the investigation were (1) to evaluate the losses in waterfowl from lead poisoning 
and (2) to attempt to reduce these losses by developing and introducing 2 nontoxic shot. Information om 
lead poisoning was obtained through study of pertinent findings already published, through experimenta- 
tion with penned ducks, figs. 1 and 2, and through extensive surveys of conditions in wild populations. 
This paper is a preliminary report on the investigation, which, according to present plans, will be 
covered in greater detail and with supporting data in a future publication. 
Contrary to popular belief, lead shot in the flesh of waterfowl does not cause lead poisoning. Shot 
pellets in the flesh undergo slight, if any, change and are of little harm to waterfowl unless they have 
damaged vital tissues. 
Lead poisoning is likely to occur in waterfowl that have swallowed lead shot pellets while feeding 
on the bottoms of lakes and marshes. After a shot pellet has come to rest in the gizzard of a bird, the 
surface of the pellet is eroded and dissolved away through the grinding action of the gizzard and its con- 
tents and through the chemical action of the digestive juices, fig. 3. The lead undergoes further chemical 
change as it moves through the intestine. Some of the lead compounds that are formed are absorbed by 
the blood stream through the intestinal walls and apparently damage the liver and kidneys. Lead com- 
pounds also appear to have a direct harmful effect on the muscles of the digestive tract. The normal 
activity of these muscles may be reduced to such an extent that adequate digestion and assimilation of 
food are seriously impaired. Lead poisoning is the name given to the pathological condition that results. 
SYMPTOMS OF LEAD POISONING 
The public usually becomes aware of lead poisoning among waterfowl through spectacular local 
die-offs of birds late in fall or in winter. Because severe weather often limits the food supply at the 
time of such die-offs, the public has frequently attributed the losses to starvation associated with scarci- 
ty of available food. Some sportsmen know that the damage done by lead poisoning is not confined to 
die-offs of spectacular proportions. They recognize that the emaciated ducks they kill during the hunting 
season -- the birds they aptly term “straw hats” -- are in poor flesh as a result of lead poisoning or 
crippling gunshot wounds. 
It is possible to recognize most cases of lead poisoning in waterfowl by observing the appearance 
and behavior of living birds and by examining the viscera of dead birds. 
Se 
