112 
Low temperatures, rain and snow probably constitute the greatest hazard to 
successful production, but data are lacking upon which to draw the proper associ- 
ations. From all that is known, the summer of 1953 seemed to be an average year 
as far as weather was concerned. 
Breeding Populations 
The breeding population survey in Quebec and Labrador was conducted 
between the dates of May 9 - 12, and May 20 - 31. A total of 4,955 miles of over- 
land transects were flown, plus 660 miles of shoreline counts. In 1952, the survey 
extended over a longer period, the data being gathered between the dates of May 2 - 
8 and May 20 - July 8. Since past experience has indicated that the number of adults 
visible on transects gradually decreases as the breeding season progresses, it 
seems probable that the number of birds observed during the 1952 survey was less 
than would have been observed if the survey had been completed earlier, However, 
the indicated increase is sufficiently great between the two years (index of 787,060 
to 1, 164, 839 or + 48 percent) and it is not likely that the difference in survey periods 
was entirely responsible. It is concluded, therefore, that there was an increase in 
breeding population in Quebec and Labrador between 1952 and 1953, although it is 
difficult to determine the amount. An examination of Table J indicates that the 
increases took place among the black ducks, scaup, mergansers, and scoter; while 
goldeneye may have decreased, 
In Table I the population index figures are broken down according to the 
number of pairs, singles and grouped birds observed. Other breeding ground surveys 
have indicated that early in the breeding season the majority of birds observed will 
be in pairs, but as the season progresses, a steadily growing proportion of the adults 
will be observed as lone drakes or as grouped birds. When surveys are conducted at 
about the same dates each year, variations in the proportion of lone drakes are used 
as measures of the relative progress of the breeding season. In the east, the black 
duck is of primary importance and the sex cannot be distinguished. It is assumed, 
however, that a single black duck during the breeding season is probably a lone drake, 
Since it is extremely unusual to see a lone female during this period. A second 
assumption included in Table I data is that two black ducks together constitute a pair. 
In areas of relatively high breeding population in the west, it is fairly common to see 
two drakes together, and it is probable that some of the paired black duck observations 
are actually two drakes, rather than a drake and ahen. With the thin density of 
breeding black ducks throughout most of eastern Canada, it is thought that the chances 
of drakes petting together is relatively slight and this factor is of little importance. 
Considering the surveys of the past two years, it is of interest to note that the 
percentage of singles was higher in 1952 than it was in 1953. This was expected in-~ 
view of the fact that the 1952 survey continued through a later date than in 1953. 
Table II presents the breeding population index figures according to the four 
strata into which the region was divided for more efficient sampling. A summary of 
the shoreline counts which were made during the two years is as follows: (although 
1,550 miles were flown in 1952 as compared to 660 in 1953, the portions of the area 
involved were roughly similar). 
