These reflect large Increases from last 
year. Stratum A Increased 94 percent 
from last year and stratum B Increased 
74 percent. Stratum C showed a de¬ 
crease of 9 percent from 1964, and 
stratum C had a significant Increase in 
pothole numbers in 1964. The Provin¬ 
cial index increased 60 percent" above 
1964 (table B-5). 
The quality of these potholes is con¬ 
ditioned by two primary factors: (1) 
water depth, and (2) existing cover. 
With low levels or nonexistent water 
from previous years the water level in 
potholes this year would be expected to 
be low and vulnerable to the vicissitudes 
of the season. Unless summer seasonal 
rains occur in good quantity we can ex¬ 
pect to lose more potholes than normally. 
This is especially true in strata A and C. 
During the dry years the use of power 
machinery in farming practices has re¬ 
sulted in the modification of many pot¬ 
holes by removing the existing cover and 
plowing previously submerged bottoms. 
Little habitat was sacred and most of it 
was affected to some degree. 
Although good runoff has reconstituted 
many potholes they will be of low quality 
to waterfowl because of the ephemeral 
nature of the water and lack of adequate 
nesting cover. Several years are re¬ 
quired to return these droughted areas 
to optimum waterfowl production. Until 
this occurs the parklands and associated 
moraines constitute the habitat most 
likely to sustain our waterfowl produc¬ 
tion. 
Breeding population indexes 
Reduced indexes, in the range of 40 
percent, are reflected in all species, 
except the pintail, both in respect to 
long-term averages and in comparison 
to 1964, (tables B-6 and 7). Paradox¬ 
ically the pintail, the species which 
suffered the most drastic population 
losses because of drought, increased in 
numbers and was 23 percent above last 
year. The pintail is still well below 
long-term averages. 
The coot index, though improved last 
year, has followed the pattern this year 
of the ducks and shows a 47 percent de¬ 
crease from 1964 and a 44 percent de¬ 
crease from average. With improved 
water conditions one would expect coots 
to increase. Copts are found only in 
potholes which will persist throughout 
the summer. This is another evidence 
of the low quality of existing habitat. 
Parkland populations continue to sustain 
the greatest proportion of coot popula¬ 
tions. 
From observed evidence mallards and 
pintails were beginning to nest in early 
May. The strength of this nesting effort 
will be reflected by July production. 
Mallard lone drake index of 82 percent 
appears to be normal when compared to 
previous years. However, the pintail 
lone drake index of 75 percent is low 
when compared to previous years. 
Weather conditions, though not critical 
for nesting waterfowl, were such that 
continued cool weather with intermittent 
rain or snow could depress or delay 
normal nesting activity or early nesting 
mallards and pintails. Observations 
have confirmed an influx of birds later 
in May. This increase was only partially 
recorded in survey data. It is possible 
that this increase could raise indexes to 
a more comparable position with last 
year, but still not equal to average 
numbers. 
To a greater extent than usual the 
relative production from this year's 
breeding population will largely deter¬ 
mine the success or failure of this water- 
fowl season. 
Waterfowl production indexes 
There was a 52 percent reduction in 
observed broods from average and a 43 
percent reduction from last year. Pro¬ 
fuse growth within the pothole basins 
may have served to negatively bias ob¬ 
served broods during this survey. 
Coot indexes increased 50 percent 
over last season, but they are still 40 
percent below average. Of note is the 
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