78 
followed by heavy rains in May, Juneand early July which maintained high water 
levels and retarded seeding throughout most of the Province. Precipitation from 
early April to mid-July ran from two to over four inches above normal, while 
temperatures were generally above normal. 
Tables I and II show the aerial pond count for May and July as compared 
to the four previous years. 
Table I.- May Water Area Indices - Southern Manitoba Aerial Survey. 
Year Ponds in Stratum A Ponds in Stratum B Total 
1951 240,500 185,900 426,400 
1952 174, 200 155, 400 329, 600 
1953 186, 600 311, 700 498, 300 
1954 258, 200 1,975, 400 1, 333, 600 
1955 314, 700 427, 700 742, 400 
Table Il. - July Water Area Indices - Southern Manitoba Aerial Survey. 
—_ 
CF 
Year Ponds in Stratum A Ponds in Stratum B Total 
1951 _ 87,200 No Record - 
1952 126, 900 No Record - 
1953 150, 900 No Record - 
1954 472,400 384, 200 856, 600 
1955 339, 300 270, 900 610, 200 
Although the data show a decrease in the number of ponds from 1954 
to 1955, there was actually more water present this year both in May and July. 
Part of the discrepancy is caused by our having counted considerable sheet water 
and ditches in 1954, mainly in the flat plains of Stratum "B"', and part is caused 
_by the fact that the flooded conditions in 1955 often were sufficient to combine 
several small potholes into one large one. 
Most of the rise in water levels occurred before the nesting season, 
and subsequent rises were not severe enough to cause extensive flooding of nests. 
The delayed seeding took place when most of the mallards and pintails were 
incubating. However, in Manitoba there is little nesting attempted in grain stubble, 
so it is probable that this was not a serious factor. 
High water considerably reduced nesting cover for diving ducks. This 
was particularly evident on the large marshes where most hard-stem bulrush and 
cattail from. the previous year was useless and the new growth delayed. However, 
