Duck Production 
It is unfortunate that data this year on the number of broods in July per breeding 
pair in May, and on the average brood size were meager (Table V). Very poor success 
was encountered in the July aerial brood counts. Not enough information was secured 
to form a reliable index to State-wide duck production. In order to obtain usuable data 
on the success of the nesting season, the July inventory will have to be revised. 
A comparison of the May and July aerial inventories in 1952 and 1953 over 
identical areas on Western Slope drainages (Table IV) indicates a 746 (10 percent) 
increase of total ducks in those areas in May of 1953, buta 1,109 (87 percent) 
decrease in numbers of young produced and a 882 (26 percent) reduction in total 
ducks observed in July. Furthermore, in May of 1952 there were nearly twice as 
many single males than paired birds, whereas pairs nearly doubled singles in May of 
1953. Finally; the average duck brood size for the State dropped from 6.4 in 1952 to 
5. 7 in 1953. 
Acutally duck production was undoubtedly considerably higher than the July 
inventory indicated. Observations of waterfowl habitat areas subsequent to the July 
inventory revealed a substantial number of young broods which were not seen during 
that inventory, indicating that spring weather conditions interferred with the normal 
egg-laying period, thus distributing the hatch more evenly throughout the summer. 
The greater number of paired ducks observed in the May inventory this year also 
suggests that the hens had not yet commenced incubation. In all probability, duck 
production in 1953, due to inclement spring weather, fell short of 1952. 
Table III. - Breeding Duck Population for Wyoming in May, 1953* 
Miles of No. of Density / Total Miles Total No. 
Stream Breeding Mile of of Breeding 
Drainage Surveyed Ducks Stream unsurveyed Ducks 
, Surveyed Habitat 
Green River 
Upper Green 

(Above CCC Bridge) 168 1,482 8.9 352 4,615 
Lower Green 
(Below CCC Bridge) 226 846 3.7 264 1, 823 
Green River Total 394 2,328 616 6,438 
Snake River ~ 192 1, 666 8.7 184 3, 267 
Bear River 70. 1, 866 26.6 16 2,292 
Salt River 74 1,470 i ee 6 1,590 
Wind River 254 1, 764 6.9 160 2, 868 
Big Horn River 294 1,508 5, l 240 2, 732 
Belle Fourche -Cheyenne 
River 188 142 8 156 267 
Upper North Platte River 
(Above Alcova Dam) 494 1,354 2.7 230 1,975 
Lower North Platte River 
(Below Alcova Dam) 373 2,672 V2 438 5,825 
North Platte Total 867 4,026 668 7, 800 
Powder-Tongue River 290 70 2 628 196 
Total 2,623 14, 840 2,674 27,450 
*Exclusive of Yellowstone National Park. 
