8 
is doubtful since there is nothing to prevent a direct f 11 Jit across any 
■ •• t • 
of the mountain passes. Share is also a general migration southward, 
probably by a comparatively stall number, of birds, over the Bocky Mountain 
Plateau, that carries the snowy herons and some of the boosts throuji the 
scattered lakes and ponds found in Utah, Sew Mexico and Arisona. 
In examining these records it must be borne in mind that many of 
the birds banded at the mouth of Bear Mver in. Utah were individuals that 
had not bred there# Drake pintails, and a few mallards begin to cost© into 
that region aft* the first week in <!u m and continue to gather, perhaps 
from points far distent, from then until late fall. Migration oat to 
other points begins about the first weak in September, and there is a 
constant shifting of the waterfowl population during the fall as birds 
arrive from the north, * leave for other points. About thanksgiving 
time the iter liver bay® begin to frees®, and in normal years by December 
1, daces are forced ait of this region. An occasional open winter may 
V | • , ; ■ - . , ' 1 ' ' , . . 1 '.' \ \ ; ■ • 
permit their sojourn- until January or later. A few birds remain to winter 
in Utah in sloughs or channels kept open by spring water but the majority 
perform extended flights to other regions, dome of the wintering mallards 
pass a short distance northward into the Snake liver drainage in Idaho. 
• Banded birds were set at liberty near the Duckvilie Gun Olub at the 
mouth of Bear liver save for a few that in 1916 were given to the state Jrtlsh 
and Game Gotaaission for exhibit ten at the Annual State Jhtr in Salt lake City, 
anti teat were subsequently set at freedom near Geneva, Utah on tee shore of 
Utah. lake. 
