ao 
advanced in 1952 and 1953 that "breeding pairs on the prairie breeding grounds 
tend to make maximum use of the available small water areas and spill over into 
less favorable or submarginal habitat when maximum capacity has been reached." 
Apparently the water areas on Redvers Area had reached maximum carrying 
capacity in 1952 and the reduction in number of areas in-1954 forced some breeders 
to move elsewhere. 
In 1954 there were 3.03 pairs per acre on wooded water areas and 2.20 
pairs per acre on open water areas. In addition to being smaller in size, the wooded 
areas were somewhat more attractive, especially to mallard in 1954, due to the 
fact that receding water levels on open areas left- barren shorelines with little or 
no concealment cover in many cases, 
Nesting Success 
Six hundred nests were located during the nesting season of 1954. Thirty-two 
percent of the nests were found by a black Labrador dog. Table III lists nest history 
data for both active and inactive nests. The former being those from which a hen 
was flushed and the nest followed through to completion. Inactive nests were again 
a poor yardstick of nest succéss due to the extreme difficulty of finding hatched-when- 
found nests in the rank, heavy cover in late June and July. 
Table III. - Nest Data Summary - Redvers Study Area Summary of All Nests Found 


by Species, 
Total Total Percent 
Species ‘Found Abandoned*® Left Destroyed Hatched Success 
Mallard 433 38 395 320 75 19.0 
B-w. teal 63 9 54 44 10 18.5 
Pintail 24 3 21 13 8 38.1 
Canvasback 29 Fs 27 13 14 51.8 
Baldpate 6 0 6 5 1 16.7 
Lesser sScaup 7 0 7 3 4 By. 1 
G-w. teal 1] 1 10 10 0 0.0 
Ring -necked 10 1 9 5 4 44.4 
Redhead 1 0 1 0 1 100, 0 
Shoveler 12 2 10 6 4 40.0 
Gadwall 5 0 5 2 3 60.0 
Totals 601 56 545 421 124 22.7 
* These nests were apparently abandoned due to the observer finding 
the nest. 
