70 
A July 15 aerial coverage (1/16-mile each side of road) was made around the 
regular transect and then parallel to the transect a mile north and a mile east. 
These coverages (corrected for air) compare as follows with the ground data for 
July 15-17: 
Actual Broods Potential Broods Total »« 
Regular Air 72 26 98 
Offset Air 40 68 108 
Ground 185 9 194 
Because of the dubious accuracy of ground data, it is difficult to assess the 
aerial work. 
Banding 
One phase of the waterfowl depredation investigations called for the banding 
and marking of locally-raised (preflight) young mallards and pintails. Between 
June 18 and August 27, two workers spent the equivalent of almost 5 weeks banding, 
on 118 sloughs, 1, 139 ducks of which 941 were preflight young of the 2 species 
mentioned above; details are presented in Table II. Until about mid-July fish-landing 
nets were used and the birds were caught either in the water or after being driven 
onto land. For the remainder of the period a Golden Labrador Retriever, owned by 
M. W. Morgan, Kindersley, Saskatchewan, was added to the crew and had to be 
credited with 5 out of every seven ducks banded thereafter: the dog caught approx- 
imately 800 birds in the 20 days he was used. 
Mr. Floyd A. Thompson, U. S. Fish and Wildlife, working with a 6-man crew, 
conducted 7 drives in the area from July 19 to 22 and August 12 to 13 and banded 
approximately 900 young ducks. As a result of the efforts of these 2 crews a grand 
total of 812 locally-raised mallards and pintails were marked by means of yellow 
plastic neckbands with black symbols. 
Most young mallards and pintails banded were aged to the nearest week, based 
on diagrams for each species prepared by L. H. Blankenship (1952 M.Sc. Thesis, 
University of Minnesota). These data have been graphed as follows: 
