UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 793 
Contribution from the Bureau of Biological Survey, 
E. W. NELSON, Chief. 
Washington, D. C. 
PROFESSIONAL PAPER. 
July 31, 1919 
LEAD POISONING IN WATERFOWL. 
By Alexander Wetmore, Assistant Biologist. 
CONTENTS. 
Introduction 
History 
Species of birds affected 
Symptoms of lead poisoning 
Page. 
1 
_ 2 
3 
3 
Page. 
Post-mortem appearance 5 
Results of experimental work 7 
Prevalence of shot in marsh, areas 9 
Conclusions 10 
INTRODUCTION. 
Lead poisoning in various species of wild ducks and other water- 
fowl has recent!} 7 attracted attention among persons interested in 
game birds in the United States. Though for a number of years this 
disease has been reported in periodicals devoted to sport and from 
other sources, it is little recognized and understood, and few sports- 
men have any knowledge of it. Already it is causing the loss of a 
considerable number of waterfowl each year, and there is no doubt 
that as time goes on it will assume greater importance. Lead poison- 
ing in waterfowl has its origin in the large quantity of expended shot 
that from year to year is deposited in the mud about shooting points 
and blinds in marshes, shallow bays, and lakes. Birds find and 
swallow these leaden pellets while searching for food, and many are 
seriously affected by the poison thus taken. Present knowledge in- 
dicates that the mallard, canvas-back, and pintail ducks and whistling 
swans have suffered most, but a number of other species will probably 
be included in the list when the matter is more fully investigated. 
Many opportunities have come to the writer to handle and examine 
ducks and other birds suffering from lead poisoning during the past 
three years, and he has had occasion to carry on experiments to ascer- 
tain the cause and manner of the affection. The results are outlined in 
Note. — This bulletin is a report of studies made of a serious malady among ducks and 
other waterfowl in the United States. It is for the information of sportsmen, naturalists, 
and others interested in game birds. 
120366°— Bull. 793—19 
