T tal figures abtained from 51 aquare miles of farm land reveal viat the 
Preduction per equare mile is 5,06 birds. 
Hiver Bottom Sectjong: Unususlly high water during the spring is thought to 
have had quite an effect on duck production, but measuring the effect of hirh 
water la impossible on ene year'a study. Ewen with this flooded conditisn, 
production was higher than on farm lends. Smaller trood sizes ere theught te 
be due to greater predator activity, 
4 Area Ho. Adulte No. Youngz 
Total Area Area Sampled —- Sampled Seen SOer 
216 13 5. ot ng 44 

To summarize the findings, the following table is prepared. 
Tota] Area Total Tetal Fraduction 
ATeA Sampled Adulte Toung pear 
Seen Seen Square nile 
Farm land 1,192 51 a 26s 5,06 
River bottom Land e.g 19 Bs 144 T.57 
Total 1,407 70 145 402 EB, 4 
The speciee percentage composition of ducke in the Seuth Platte River ares 
is recorded to be: Mallard, 47.7: blue-winged teal, 26.8; ruddy duck, 6.9; 
piatall, O.4; gadwall, 6.4; and other efeciles including unidentified ducka, 3.9. 
Other reports of duck broed obeervation in northern Oolerade revealed 99 
broode with 527 young. The average number of young per brood is 5,42, Taking 
data from all sections of northern Coloraéde, ineluding the Seuth Flatte River 
etudy area, a congervative estimate of 20,000 hae heen made for duck preductien, 
Scattered reperte frou the otuntainous areas give a breed arerage of 
7.ed,. 
Misration records were kept in both the South Platte River and San Luis 
Valley study areas, but the fnformatien chtained is not considered conclusi¥e, 
Anslyain 
There 1s considerable hesitancy to state facte and figures regarding 
total numberg of ducke or production. It is felt that the lack of peesitire 
techniquee and methode now being used and the preeence of many rariablesa makes 
Erejection of data unreliable. ‘impleying well-ceordinated factual greundwork 
ond aerial census in the future hes some promice of producing what may be ueed 
Ae & conrergion factor for determining psepulatione or production. 
