117 
Table 5 -- Comparison of Brood Production by Aerial and Ground Surveys 
a a a ee ey 
Poe Total Broods Seen Broods Per Square Mile 
Ground Aerial ** Ground Aerial 
1 34 12 Sant 1.3 
2 21 16 2.3 1.7 
3 16 12 6.1 4.6 
4 56 68 8.9 10.8 
* 32 0 3.7 
Total 170 140 4.8 39 
** Aerial count made on 1/8-mile strip - figures doubled to make 
them comparable to ground strip of 1,.4-mile. 
* Broods plus feigning females. 
Based only on the five study areas listed above, it would appear that on the 
prairies aerial and ground observation of broods was almost identical, while aerial 
observation recorded 62 percent of the breeding waterfowl present. In the parklands, 
the aerial crew found about 56 percent of the broods and 53 percent of the breeding 
waterfowl located by the ground crew who utilized the "beat-out'' method. 
Weekly censuses of breeding populations as well as weekly brood counts 
show wide variations in monthly, weekly and even daily waterfowl populations on 
individual habitats. This wide range of area utilization of a habitat by breeding 
birds throughout the summer months and of broods during June, July and August 
makes it extremely difficult to establish definitely the resident population of 
districts as small as these study areas. The movement of broods into and out of 
a particular pothole is a constant occurrence. This localized overland migration 
occurs particularly at the period when the brood reaches a Class [I size. Never- 
theless, broods hatched on or near one pothole may move overland within the period 
of one week, to another pothole or lake one quarter or more miles away. This is 
true not only among the puddling ducks but also among.such divers as redheads, 
canvasbacks and scaups. Observations over a six year period on the Alberta 
waterfowl breeding grounds lead one to believe that isolated lakes and ponds are 
about the only habitats where brood histories can be kept with any hope of real 
accuracy. Districts where potholes are present in large numbers and in close 
proximity to each other are the scene of widespread and repeated local migrations 
of females and their broods. This migration is of such proportions and duration as 
to preclude the possibility of following the history of a population known to nest on 
or around a study area whose dimensions are linear in nature. 
Summary 
1. Three intensive ground study areas in the parklands were selected for 
observation during the Alberta waterfowl breeding season of 1952. These areas 
were under continuous study during May, June and July. Data was recorded on such 
subjects as: weekly changes in breeding waterfowl populations, ecological aspects 
of the waterfowl habitats, water levels of potholes, land use of the study area, nests 
and nest histories, hatching success and brood survival, as well as weekly records 
of brood utilization of the study areas, 
