20 BULLETIN 936, U. S. DEPABTAIEXT OF AGRICULTURE. 
In general, it may be said that conditions on the Bear River 
marshes are favorable for the attraction and preservation of a large 
number of wild ducks. This area may be likened to the lower end of 
a great funnel, that, drawing its supply of waterfowl from Salt 
Lake Valley and also from a broad area to the north, concentrates 
the hirds here until they spread in migration to other regions of the 
West. That these birds do range widely after leaving these marshes 
has been shown by records of ducks that have been banded and 
released here and subsequently have been shot elsewhere. 6 Eecords 
thus obtained show that birds released near the mouth of Bear River 
in migration cover the region from Oklahoma and Texas west to the 
Pacific coast in California. 
6 During an investigation of the duck sickness .mentioned as occurring on these marshes, 
a considerable number of ducks were banded and released. The aluminum bands 
used are placed securely on the legs of the ducks. These hands are of two types, each 
bearing a number on one side ; the reverse in one style is inscribed " Notify U. S. Dept. 
Agr., Wash., D. C," and in the other,. " Notify Biological Survey, Washington, D. C." 
It is hoped that sportsmen killing ducks marked in this way will forward the bands 
at once as directed, with information as to date and place of capture and any otber 
details that seem relevant. Valuable information is available from such return records 
as to lines of migration, longevity of individual birds,, and other points of value in 
study of conditions affecting waterfowl. 
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