Flyway provide a measure of production 
success for mallards as far back as 1939, 
These data demonstrate that production ratios 
can vary from a high of about 4 young a pair 
of adults during periods of good breeding 
habitat conditions to a low of about 1 young 
a pair in the fall flight. In 1960 there was 
considerable improvement when 2.6 young 
a pair were recorded. In 1961 and 1962 
the ratios were quite similar, averaging about 
1.4 young a pair. 
Total annual mortality can be determined 
from banding. When information on produc- 
tion ratios obtained from the wing collection 
survey is combined with a measure of 
mortality from banding, a comparison of the 
two rates provides a measure of the net 
change in population levels which can be 
expected in a given year. The decrease 
in population level since 1958 is confirmed 
by this approach. 
Thus, the Bureau is not dependent on a 
single source of information for determining 
the answers to many population status prob- 
lems, A series of surveys are now operating 
which complement each other to a marked 
degree, When data fromtwo or more sources 
agree, greater reliance is placed on the re- 
sults. When they disagree, often the reason 
for the discrepancies can be understood, 
A subject of considerable importance is 
the effett.of kill by hunters on waterfowl pop- 
ulation levels. For several species of resi- 
dent game there is anaccepted game manage- 
ment principle that kill by hunters has little 
effect on the number of birds that will be 
available the following fall. This is not the 
case with waterfowl. During the past year, 
research at the Migratory Bird Populations 
Station, Laurel, Maryland, has demonstrated 
conclusively that survival of several species 
of waterfowl important to the hunter has been 
controlled to a marked degree by means of 
appropriate shooting regulations, The evi- 
dence is clear that for several important 
species of waterfowl, a high portion of the 
birds will survive from one year to the next 
if they are not shot, This is important dur- 
ing periods of low production, suchas the one 
just experienced, It is clear also that even 
with decreased populations, the gregarious 
nature of waterfowl causes them to concen- 
trate in many locations where liberal regula- 
tions would result in a large kill. During 
periods of low production, a large kill could 
have no other result than to reduce the 
breeding population the following year, The 
Bureau has concluded that shooting regula- 
tions constitute a powerful and most neces- 
sary tool for managing the waterfowl re- 
source, 
There seems no question but what the back- 
bone of the drought period has been broken. 
The May pond count in the southern portions 
of the Prairie Provinces increased 17 per- 
cent as compared to 1962, but is still 36 
percent below the average for the period 
1951-1962 and 60 percent below the peak 
level recorded in 1955. Rains during the 
summer period increased the July count 
this year by approximately 100 percent 
over the average of the previous 12 years 
and 52 percent below the peak level reached 
in 1955 (figure H-3, p. 165), 
In the Dakotas and western Minnesota, the 
May pond count increased 18 percent as 
compared to last year, while the July count 
increased 7 percent over the previous year, 
However, water conditions in the eastern 
Dakotas and Minnesota improved greatly last 
year, which means that the count this year 
represents improvement over a _ situation 
that was already favorable, 
For the most part, weather conditions 
favored production this year. The weather 
was mild in late April and early May 
throughout much of the pothole breeding 
range, fostering early nesting. Although a 
heavy snowfall on May 19 in some pothole 
areas followed by temperatures of 20° or 
lower throughout much of the important Can- 
adian breeding areas a day or so later, may 
have disrupted nesting. 
Above-average precipitation during the 
summer throughout most of the pothole 
breeding range resulted in a moisture con- 
dition which fostered renesting. Also, this 
precipitation will provide a soil moisture 
condition favorable to runoff next spring. 
FALL FLIGHT FORECAST 
General 
In Alaska, a 
breeding population was 
15 percent reduction in 
recorded during 
May. However, weather conditions were 
favorable during the nesting and brood period 
and production is expected toincrease mark- 
edly as compared to the poor success 
