
CONCLUSIONS 
The preceding discussion has dealt with three major questions: What is 
the value of typical pothole country to ducks? What are the relative values 
of the various pothole types? What is the effect of the pothole-drainage 
program on ducks? 
Value of the study area as production habitat 
The study area has considerable value to ducks: in the four years of the 
study, there was an average annual production of 140 young ducks per square 
mile. Although the productivity of the individual pairs resident on the area 
in the spring was low, about one young per breeding adult, there is not enough 
known about the previous history of these birds to conclude that this is due 
to weaknesses in the habitat itself. Many of the birds arrive rather late in 
the season, and Stoudt? points out that many birds that nest in the James 
River Valley early in the spring are later forced to leave as their nests are 
destroyed by agriculture and as the water areas dry up. It is probable that 
many of the pairs using the Waubay area for nesting are these same birds and 
already have had their productivity reduced by at least one unsuccessful 
nesting attempt. The fact remains that on a square-mile basis there were con- 
siderable numbers of young produced here. 
Relative values of pothole types 
The general statement may be made that on an area basis, all types of 
potholes are of practically equal value. The small temporaries are of no 
value through most of the year but, acre for acre of water, they are the most 
valuable type during the critical breeding period. The large permanent areas 
serve a number of functions in duck production through a much longer period, 
but do not have as high a value during the breeding season. Furthermore, as 
water levels, weather, and duck populations fluctuate, the birds vary their 
use of the habitat, further equalizing the long-term values of the different 
types. 
Effect of the drainage program on ducks 
Drainage of any water area reduces both the total number and the aggregate 
area of potholes and has an adverse effect on duck production, particularly 
as it relates to the carrying capacity of the habitat for breeding pairs. 
There is no phase of the reproductive cycle that can be shown to benefit by 
this progran, regardless of claims that brood areas are improved by it. 
It should also be pointed out that the public funds that are contributing, 
through drainage of potholes, to the elimination of a valuable national re- 
source are also contributing to the maintenance of a form of agriculture that 
many believe to be detrimental to the economic future of the region. Agri- 
cultural authorities and soil conservationists have stated that the best use. 
of this land is the raising of grass and cover crops. Anything that helps to 
perpetuate the present type of farming, row crops and small grains, is only 
delaying the ultimate shift to a better use of the land. 

4Stoudt, J. H. 1950. Letter to the Director, U.S. Fish and Wildlife Service, 
relating to the 1950 breeding-ground survey. 
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