
69 
Before presenting the resulting data, another complicating factor must be 
explained: On July 17, 1953, two investigators drove 272 +or - young of 6 Species 
from a dense stand of spikerush (Eleocharis, sp.) into open water just long enough 
for them to be counted without getting species or age data, Three days later, 
Floyd A. Thompson, U. S. Fish and Wildlife Service, with a 6-man crew trapped 
365 + gr - young in the same patch of cover; possibly 20 or 30 birds escaped. The 
youngest ducklings were released immediately and then 98 shovelers, 88 pintails, 
55 blue-winged teal, 36 mallard and 10 baldpates were banded. The writer has not 
the age classes for the 287 birds banded nor a species count for the 80 + or - ducks 
not banded. This one area held 30 percent of the broods on the transect. 
The data calculated from the June and July brood surveys are as follows: 
Actual Broods Potential Later Broods 
Pintail Mallard Other & Pintail Mallard Other & 
Unident. Unident. 
June 10-11 Class I 76% 42%* 5%* 140+ 152+ 272+ 
July 15-17 Class I 8* 13* 13* 0 3% 6* 
" Class II 6%* 19* 10* 
wt Class III 25 10 2 
" Feigning Females 3 5 11* 
July 20 Special Area 16 6° 38% 
July Total 58 53 74 Total: 9 Total: 194 
*xFigures used to compute minimum brood density for area (cf. below). 
Based on the July coverage only, a density of 9.5 broods per square mile is 
obtained. That the July data are not reliable is evidenced by an examination of the 
pintail-mallard figures: In June, 118 broods of these 2 species were seen and at 
least 292 potential later broods indicated; by the time of the July coverage the 118 
actual broods would have been in age class III but still not flying, and yet only 35 
of them showed up. Also more actual broods of these 2 species were recorded in 
June (118) than in July (111 plus possibly 6 others from the unbanded young on the 
area described above) in spite of the fact that at least 46 additional Class I and 
Class II broods had hatched between coverages. 
Because of these difficulties the best production figure available for the 
Kindersley-Eston study area is a minimum of 12.2 broods per square mile -- 
52 percent of the 1952 figure (23. 5). This density was compiled from the figures 
marked with an asterisk in the above table, Class III July broods were omitted to 
avoid duplication of counts; because of this it was felt desirable to omit mallards 
and pintails of unknown age banded on the area described above and feigning hens 
of these species elsewhere on the transect; feigning hens of other species were 
included because of the low percentage of Class III's among known-aged broods. 
Ground-To-Air Comparisons 
Be iets ater ia oi RL 
As can be seen from Table I, the over-all breeding pair decrease from 1952 
to 1953 is essentially the same whether calculated from ground or air data, However, 
an examination of individual species trends brings out discrepancies. While diametri- 
cally opposed teal figures may not be important in this district, those for mallards 
(+22 percent as compared to +57 percent) would seem to be more serious. 
