175 
estimates were made is small for some habitat types; however, future plans for study 
in this area include increasing the size of sample, and determining correction factors 
for time or season to adjust counts for the total production, 
| Estimates of total 1953 production in North Park reveal 5,675 breeding -pairs, 
and 3,736 broods with an average brood size of 6,12 resulting in the production of 
22,864 young. Breeding-pair success is, thus, indicated as about 66 percent, No 
comparison of total Park production is available for past years. 
Species composition of observed broods is listed in Table II. This list compares 
favorably with past years showing that the baldpate is again the most common producer 
with mallards second. 
Table II. - Species Composition Observed Broods, North Park, August 4-6, 1953 
(Not projected) 


No. No. Average Percent Composition 
Species Broods Young Brood Size of identified young 
Baldpate 60 360 6.00 36.2 
Mallard 36 219 6.08 22.0 
Gadwall 22 133 6.05 13.3 
Pintail 22 131. 5.95 13.1 
Green-winged teal 10 : 65 6.50 6.5 
Canvasback 4 24 6.00 2.4 
Scaup 4 22 5.50 2.2 
Shoveler 5 21 4.20 2.1 
Redhead 3 16 5.33 1.6 
B-w. or Cinn. teal 1 6 6..00 .6 
Unidentified 73 %* 472 6.47 -- 
Total 240 — 1,469 6.12 100.0 
Tot. Est. Production 
North Park ** 3,736 22, 864 6.12 

* Lake John counted by air ~- no species identification (57 broods). 
** Based on ground counts August 4-6, 1953, projected by habitat type 
and corrected for time of season when count was made, 
South Platte Valley 
The South Platte Valley, located in the northeast corner of the State, is composed 
mainly of habitat types typical of irrigated lands. Total land area under consideration 
amounts to 1,407 square miles of which 5 percent or 70 square miles were intensely 
studied from the ground. | 
Results from aerial breeding-pair counts along the South Platte River this 
spring, indicated about 50 percent more pairs in the area this year than during a 
comparable count in 1952, This striking increase did not carry over to the production 
of young. Apparently the early surplus of pairs were forced to move elsewhere to nest 
by the decrease in habitat which was noted during ground surveys. 
