60 
Summary of Active Nests Only 

Total Number Percent 
Species of Ac tive Nests Destroyed Hatched Success 
Mallard 266 202 64 24.1 
Blue -winged teal 39 29 10 25.6 
Pintail 19 12 7 36.8 
Canvasback 25 12 13 52.0 
Baldpate 6 5 1 16.7 
Lesser scaup 7 3 4 57.1 
Green-winged teal 8 8 0 0.0 
Ring-necked 9 5 4 44.4 
Redhead 1 0 1 100.0 
Shoveler 10 6 4 40.0 
Gadwall 5 2 3 60.0 
Total 395 284 111 28.0 
The extremely high nest destruction in 1954 was due primarily to the 
weather. First nesting attempts of the mallard were broken up by the blizzard and 
zero temperature of May 1. May and June were characteristized by cold, very wet 
weather which retarded the development of good nesting cover. In addition, the dry 
fall of 1953 and the following winter encouraged and enabled the farmers to doa 
terrific amount of burning. Burning coupled with low pond levels left only a narrow 
strip of grass or cattails around the pond margins. This condition allowed easy 
access to nests by predators. Also, the cold weather retarded development of other 
predator food such as herbs, young mice and ground squirrels, insects, etc. which 
caused predators to turn in greater-than-normal intensity to duck nest hunting. 
Then too, actual flooding of nests was a serious factor in 1954, 
Nest Destruction for all Species by Causes 
Crows and Magpies 33% Flooding 11%  Desertion 2% 
Skunk 32% Other mammals 4% Burning 1% 
Ground Squirrels 12% Unknown 4% Road construction 1% 
From the data in the following table we find that nest success was considerably 
lower for nearly all species in 1954, Nest success for the mallard in 1952 might be 
a bit high due to the fact that few nests were found before the 15th of May. 
