
213 
Brood size data of the first brood counts for the past four years are 
summarized as follows: 
Year Class I Class II Class III All 
1952 7.3 7.8 6.6 7.4 
1953 . 7.3 7.2 6,2 tae 
1954 ‘3 x ee ral | 6.0 | 7.5 
1955 8.5 39 T.9 8.0 
The 1955 average brood size of 8.0 indicates that this year's broods 
averaged considerably larger than usual. The 1955 brood size data is based ona 
total of 180 aged broods. The number of broods by species is as follows: mallard, 
85; blue-winged teal, 32; goldeneye, 29; canvasback, 13: ringneck, 5; baldpate, 4; 
pintail, 4; redhead, 4; wood duck 2; black duck, 1; hooded merganser, 1. 
The earliness of the hatch is indicated by the fact that 18.9 percent 
of the broods were of Class III compared with 1.5 percent in 1954. The percent 
distribution of the broods by age classes is as follows: | 
Year Glass I Class II Class III 
1952 33.6 45,7 20.7 
1953 61.8 32.4 5.9 
1954 | 62.8 35.8 1.5 
1955 40,0 41.1 18.9 
The nature of the hatch is best illustrated by the hatching curve pre- 
pared from the data of the three brood counts (Figure 1). The data for each brood 
count area was considered separately, and broods observed on the second or third 
counts were eliminated if hatching dates indicated they may have been recorded on 
an earlier count. . 
. Considering all the broods the peak period of hatching was the week 
of June 7 to 13. The peak period in 1953 was the week of June 21 to 27. 
