Breeding populations indexes 
SOUTHERN ALBERTA 
The overall duck population decreased 
21 percent from that of 1964. All 
species decreased except buffleheads, 
mergansers, gadwall, and ring-necked 
ducks. 
Gadwall occur only in the most south¬ 
ern stratum and are numerically unim¬ 
portant in the area. Buffleheads and 
ring-necked ducks are regular northern 
breeders in the area south of the Arctic 
Circle, and mergansers are common 
breeders throughout the survey area. 
There is no explanation for these ap¬ 
parent discrepancies. The fact that four 
species out of a total of seventeen in¬ 
creased, representing only slightly more 
than one-tenth of the total population does 
not materially change the overall down¬ 
ward trend of ducks in general. The 
largest decreases were noted in scoters, 
mallards, baldpate, shovelers, green¬ 
winged teal, canvasback, blue-winged 
teal, oldsquaw, redheads, and ruddy 
ducks. Like the gadwall, ruddy ducks, 
redheads, blue-winged teal, and canvas- 
backs are numerically unimportant in the 
area. 
All strata registered decreases in 
total duck populations except the Atha- 
baska and Mackenzie Deltas, the Pre- 
cambrain Edge, and the Upland Tundra. 
These four together represent less than 
one-twentieth of the total area, and even 
though these are premium habitat they 
are not of great enough magnitude to 
change the overall picture. 
Coots decreased considerably but are 
insignificant numerically in the area. 
Canada geese decreased 15 percent and 
swans increased 15 percent. Twice as 
many white-fronted geese were recorded 
than in 1964. However, we consider all 
goose figures unreliable as the sampling 
plan is geared to ducks rather than geese. 
Table B-4 gives a species and area 
breakdown compared with 1964. 
Data supplied by K. Duane Norman and 
G. Hortin Jensen, Bureau of Sport 
Fisheries and Wildlife 
Weather and habitat conditions 
Drought conditions have been extant 
over southern Alberta for approximately 
half a decade. It has been widespread 
and persistent and only the northern 
parklands were excluded. Lasting re¬ 
covery from these adverse weather pat¬ 
terns cannot be complete in a given year 
but must await a succession of years 
where each shows an improvement over 
the previous year. Anything less is sea¬ 
sonal and inconsequential. 
The snowfall during the preceding 
winter was the second heaviest (88. 7 
inches) on record with a maximum of 21 
inches of snow pack. Because of this 
large accumulation of snow, this year 
gave an excellent spring runoff into the 
potholes. The result raised water levels 
in existing potholes, recreated dry pot¬ 
holes, and even produced new ones that 
were nonexistent in the past 20 years. 
Sheet water was common. 
Current spring temperature conditions 
have been colder than normal with many 
nights being near freezing. Precipitation 
has not been excessive but it was cold 
enough to have intermittent rain and 
snow during the month of May. Severe 
winds of approximately 80 miles an hour 
were recorded in south-central Alberta 
during mid-May. Consequently, the 
spring season was characterized as cool 
and delayed. Conditions have favored 
economy of water. Pothole water levels 
have remained constant or increased 
during the survey period. 
The numbers of potholes have gener¬ 
ally increased from last year with the 
greatest increase in the northern half of 
the survey area. Stratum A is average; 
stratum B is 27 percent above average; 
stratum C is 4 percent above average; 
and conditions in the southern half of the 
Province are 16 percent above normal. 
4 
