157 
This section of river, fed by heavy flows from the Owyhee, Boise, Payette and 
Weiser Rivers, was in flood stage during the last two weeks of April. The river 
level at Weiser, Idaho was the highest since the flood of 1910. Approximately 
one~third of the goose nests under observation in this area were flooded out by the 
high water. Even with this loss, the total production here was estimated to be very 
nearly that of 1951. The increase in nesting pairs more than offset the unusually 
heavy loss due to flooding. 
The nest success ratio (75.8 percent) at Blackfoot Reservoir, while not as 
favorable as 1951 (81 percent), is very close to that observed in 1950 (76 percent). 
No comparison can be drawn on the basis of total nests since several more islands 
were searched this year than in any previous year. 
As in 1951, one large island was searched for nests in Island Park Reservoir. 
Last year, 42 nests were found but only 16 were located this year. There is no reason 
known for this drop in nesting birds. , 
Brood Counts 
Waterfowl brood counts were taken by Biologists, Federal Refuge Personnel, 
and Conservation Officers with primary emphasis being placed on determination of 
brood survival. The results given in Table II are from southern Idaho only. Lack 
of personnel prevented the gathering of an adequate sample from the northern part 
of the State. 
. Banding 
In cooperation with G. Hortin Jensen, Flyway Biologist, Fish and Wildlife 
Service, Canada goose banding work was continued on Blackfoot Reservoir and Island 
Park Reservoir. Some late summer duck banding on Island Park Reservoir was done 
by Elwood Bizeau. The results are given in Table III. 
Table I -- Results of Canada Goose Nesting Survey in Idaho - 1952 
Glenns Hivwwedile Blackfoot ' Island Pans 
Ferry Reservoir Reservoir 
No. nests found 24 208 103 16 
No. nests terminated 24 205 99 16 
No. successful nests 16 (67%) 103 (50%). 75 (76 %) 12 (75%) 
No. unsuccessful nests 8 (33%) 102 (50%) 24 (24 %) 4 (25%) 
Average clutch 5.8 5,2 5.0 4.3 
Average hatch 5.1 4,7 4.7 4.0 

