Of the living birds, recovery was more rapid in victims of deliberate starvation than in those 
suffering from lead poisoning. 
SUBSTITUTES FOR COMMERCIAL SHOT PELLETS 
Lead, arsenic, and antimony are the three metallic components of commercial shot pellets. Of 
these, only lead produces ill effects when fed to ducks; tests showed that arsenic and antimony in quan- 
tities greater than ducks would be likely to ingest along with lead shot under natural conditions were not 
injurious. Efforts were made to develop alloy shot that would either neutralize the effect of lead or 
hasten its elimination from the gizzard. 
Disintegrating Shot Alloys. -- It has been suggested in the literature that if magnesium is used in 
commercial shot pellets in place of arsenic and antimony, an alloy will be produced that will disinte- 
grate in a duck’s gizzard and be eliminated harmlessly within a day or two. When fed to ducks eating 
grain diets, however, pellets containing 2 per cent magnesium were found in our study to fragment slow- 
ly and produce severe cases of lead poisoning, possibly as a result of the increased surface area of lead 
exposed in the gizzard. Other pellets of this magnesium content failed to disintegrate in natural waters 
within a reasonable time, thereby removing the possibility that they would be unavailable to ducks feed- 
ing in shot-over areas. 
A disintegrating alloy of lead-calcium also was experimentally produced and fed to mallards, but 
results were similar to those following the use of commercial shot. 
Other Alloys. -- The poisoning effect of pellets made of a lead-tin-phosphorus alloy was tested 
because patents covering the manufacture of this alloy claimed that, when ingested, it would be nontoxic 
to waterfowl. However, the mortality rate for game-farm mallards dosed with this shot alloy proved to 
be higher than that for game-farm mallards dosed with commercial shot. 
Lubaloy shot, a commercial product consisting of a lead alloy thinly coated with a copper alloy, 
was no less toxic to mallards than commercial shot. The copper alloy was soon worn away by gizzard 
) action, exposing the lead to erosion. A slight advantage was obtained in that the copper alloy delayed 
the availability of lead within the gizzard for about 4 days. 
Large doses of iron shot produced no ill effects when fed to wild mallards. Iron shot pellets 
are not at present commercially available, but further research is being conducted on their produc- 
tion and use. 
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