Breeding Populations 
Trends in breeding populations of ducks may be deduced from brood counts 
taken on a series of key areas, wh’ ch approximate 10 percent of the total water- 
fowl habitat in the Upper Columbia. Valley. The maximum number of broods geen 
in any one comrlete coverage of the vey areas is given in Table 4. Comparison 
of the figures for 194€ and 1949 indicates a slight reduction in populatione of 
mallard, Barrow's golden-eye, and bufflehead, the three most common ducks in the 
area, and an increase in baldpate, blue-winged teal, and canvasback. These 
trends were also indicated by counts of adulte made dvring early May. 
The breeding population of Canada geese hae been estimated on the vasis 
of nests counted on a sample area. The sample count in 1948 was 25, and in 
1949, 22. The estimated total breeding population was 830 in 1948 and 730 in 
1949, The degree of error in converting the sample to an estimated total may 
be considerable. 
Breeding Season 
Although the Columbia River and the adjoining sloughs were ice-free 
slightly earlier in 194° than in 1948, appearance of first broods in 1949 was 
not generally earlier than in 1948. First broods eeen were as follows; 
mallard (1 week old), June 13 (a clutch was known to hatch on May 25); 
baldpate (2 weeks old), July 6; blue-winged teal (newly hatched), June 28: 
Barrow's golden-eye (newly hatched), May 26; and bufflehead (newly hatched), 
June 13. Late broods seen were as follows! mallard (8 weeks old), August 15; 
baldpate (4 weeke old), August 5; blue-winged teal (3 weeks old), August 1: 
canvasback (4 weeks old), July 27; Barrow's golden-eye (4 weeke old), July 27: 
and bufflehead (3 weeks old), July 26. The preceding data suggest that the 
nesting season was relatively undisturbed by the operation of decimating 
factors. 
Breeding Success 
During the early summer a number of nests of waterfowl were found and 
the following clutch averages determined: mallard, 7.6 (average of 6); blue- 
winged teal, 9.3 (average of 3); and American coot, £.6 (average of 6). 
The average number of eggs in 49 complete Canada goose clutches was 
5.5, while the average hatch of 45 of theae clutches was 4.0. Data relating 
to egg loss in geese has not yet been completely analyzed, but it may be 
stated that infertility and death of the embryo are of major importance. 
Average sizes of all broods counted in the Kootenay region in 1949 are 
given in Table 5. The majority of the data included are from the Upper 
Columbia Valley. Since few counts of older broods have been made, average 
sizes of these broods, as given, may be misleading. Survival of mallard, 
blue-winged teal, canvasback, Barrow's golden-eye, and coot is satisfactory, 
considering the breeding characteristics of the epecies involved. Survival 
of bufflehead was less satisfactory in 1949 than in 1948. Survival of goslings 
was significantly better than in 1948 when the average size of 42 one-to-four- 
week-old broods was 0.5 less than this year. There is no evidence of any 
outstanding mortality factor operating against young ducks or geese. 
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