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WATERFOWL BREEDING GROUND SURVEY IN NEVADA - 1950 
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ai | Fred E. Wright * 
Introduction 
Examination of Nevada's waterfowl breeding grounds was inaugurated this year 
to determine its contribution to production. Previous investigations in the State have 
been limited to the Ruby Lakes National Wildlife Refuge and last year to the Sheldon 
National Wildlife Refuge and Stillwater Wildlife Management Area,.Fallon.. The studies 
conducted at Stillwater Wildlife Management Area have a two-fold purpose; (1):To help 
guide and evaluate the development work being carried on, and aid in planning manage- 
ment by determining the type of habitat used by waterfowl; (2) To establish production 
trends and appraise the changes brought about through development work. 
This year the State's investigation has laid the ground work for establishing 
trend areas. Coverage was only superficial in most areas through necessity, with 
emphasis being placed on the northeast corner of the State. At present it is possible 
to arbitrarily divide the State into four geographical units (see map). These units are 
more or.less separated by arid regions containing water areas on a very limited scale. 
Other geographical units exist, but their value as production areas is slight, as they 
are small and scattered. 
The units were chosen on the basis of the most abundant type of habitat. Unit 1 
is predominately reservoirs and some irrigated meadow land; Unit 11 is mostly river- 
bottom (irrigated meadow) and reservoir, but includes the Ruby Marshes, a key area. 
Unit 111, is made up of lakes and meadow land, and Unit 1V, irrigated farm land and 
marsh; and contains the Stillwater marsh which is a key area. Trend areas have or 
will be established in each of the four units. 
Investigations were carried on from June 1, through August 31, 1950, in Unit 1l. 
This area comprises the head waters of the Humboldt River drainage, and was selected 
because the habitat was relatively concentrated, enabling coverage of more area ina 
given time. Workin Unit 1V, Stillwater Wildlife Management Area, was conducted 
May 15, through August 7, 1950. 
Methods 
River and Reservoir Survey 
Aerial transects were established (see map) on the tributaries and forks of the 
Humboldt River, with the limits of each one at definite land marks. The plane used was 
a Cessna 140 and the pilot observed whenever possible. The observer has access to 
only one side of the plane and it was found advisable to fly a section of the river cover- 
ing a third or half of the habitat and then turn with the observer still in a position to see, 
and return to the start of that section. This required flying over the wider sections of 
the river bottom two or more times which resulted in a more complete coverage. Very 
few birds were moved by the activity of the plane, but many broods did seek cover as 
the plane flew over them, making species identification difficult. 
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* Information was contributed by LeRoy Giles and David Marshall, Biologists, 
U. S. Fish and Wildlife Service personnel, (S.W.M.A.) and Refuge personnel at Ruby 
Lakes, N.W.R. Pilots were Joe Rabb of Nevada Fish and Game Commission, Big Game 
Technician and Virgil Hart, Student Assistant. -Earl Dudley, State Game Warden aided 
in ground work, 
