UNITED STATES DEPARTMENT OF AGRICULTURE 



| BULLETIN No. 672 ffi 



Contribution from the Iturcuu of Biological Survey 

 E. W. NELSON, Chief 



f 



Washington, D. C. 



PROFESSIONAL PAPER. 



June 21, 1018 



THE DUCK SICKNESS IN UTAH. 



By Alexander Wetmore, Assistant Biologist. 



CONTENTS. 



Introduction 1 



History in Utah « 2 



Reports from other regions 5 



Outline of field work 6 



The duck sickness 7 



Symptoms and description 7 



Areas where sick birds are found 11 



Species affected 11 



Page. 



The duck sickness — Continued. 



Untenable theories 13 



The cause 15 



Remedial measures 1* 



Increase of summer water in streams .... 19 



Drainage of affected areas 19 



Cure of sick birds 20 



Release of banded birds 25 



INTRODUCTION. 



Since 1910, annual losses from disease of large numbers of wild 

 ducks in the Salt Lake Valley have attracted much attention from 

 sportsmen and others interested in waterfowl. Thousands of these 

 birds find suitable breeding grounds in the marshes formed in the 

 deltas of the rivers draining into Great Salt Lake, while the great 

 extent of these areas and the abundant food supply found there at- 

 tract vast hordes of others that pass in migration during spring and 

 fall. Early reports of losses from disease among these birds were ex- 

 aggerated in many cases, but it soon became evident that ducks were 

 dying in such numbers as to make it a serious matter. In the first 

 years the trouble was little understood. Various theories advanced as 

 to its cause were one by one rejected. Local interest was greatly 

 aroused, and many attempts at investigation were made. It was 

 recognized that the problem was of great importance, as a serious 

 mortality among wild ducks in Utah would soon be reflected in a 

 dimhiution in their numbers in other regions, some perhaps far 

 distant. 



Dead ducks from the affected areas were sent in to the Biological 

 Survey and were transmitted to the Bureau of Animal Industry for 



Note —This bulletin is a final report on an investigation of mortality among ducks and other water- 

 fowl in marshes about Great Salt Lake, Utah. It is for the information of sportsmen and others interested 

 in the conservation of game birds. A preliminary report was published in 1915 as Department Bulletin 

 No. 217. 



46651°— 18— Bull. 672 1 



