Breeding Population Indexes 
Table E-22 (p. 122) presents asummary of 
the duck breeding ground survey for 1963. The 
estimated breeding pair population for 1963 
shows an increase of 66 percent from 1962 
and an increase of 79 percent from the 
1955-1962 average. 
The total number of ducks counted is 
computed by combining the number of breed- 
ing pairs with birds that are found ingroups. 
It will be seen that the total number of birds 
counted in 1963 is 297,675, or 49 percent 
above the estimate for 1962. Furthermore, 
this figure represents an increase of 72 
percent from the previous 7-year average. 
Table E-23 (p. 123) indicates the long-term 
breeding ground trend for geese in Wyoming. 
In 1963 an increase of 47 percent was 
recorded over 1962 and an increase of 76 
percent was registered over the long-term 
average. 
Production Indexes 
Production surveys conducted on the Snake 
River, Bear River, and Ocean Lake indicate 
a loss of goslings on the Snake River because 
of nest flooding, and a significant increase in 
production on the Bear River, and no change 
at Ocean Lake. No production surveys were 
made on ducks, 
Conclusions 
Water and range conditions were at high 
levels over most of Wyoming, with the ex- 
ception of isolated areas. 
Early flights of ducks through the State 
were reported to be as large as any witnessed 
in the last 10 years. 
Ducks were recorded in greater numbers 
on existing areas and it was concluded that 
the fall flight of ducks from Wyoming will 
be one of the best ever. 
Canada goose populations in Wyoming are 
at the highest level ever recorded since 
surveys have been made. It appears that the 
fall flight of geese from this State will be 
the greatest ever experienced. 
COLORADO 
Data supplied by William H. Rutherford 
Colorado Game and Fish Department 
Weather and Habitat Conditions 
Weather conditions in Colorado during the 
spring and early summer were considered to 
be excellent for waterfowl nesting and produc- 
tion, Water conditions were considerably 
poorer than last year, since the State ex- 
perienced one of the driest winter and spring 
seasons on record. Fortunately, reservoir 
storage was good, and spring runoff water was 
sufficient to provide adequate water areas 
for nesting habitat. In eastern Colorado and 
the San Luis Valley, most sloughs and ditches 
were full, and most reservoirs contained 
water. In North Park and on the western 
slope, sufficient early water was available 
for meadow flooding. At the date of this 
writing, reservoir storage was dwindling, 
the high-country snow pack was rapidly 
diminishing, and precipitation was far below 
normal, It is expected that midsummer water 
supplies will be generally short over the 
State, with some areas becoming critical, In 
summary, overall weather and water condi- 
tions in Colorado seem to point toward a good 
year for waterfowl hatching, but a poorer year 
for later brood rearing. 
Breeding Population Indexes 
Examination ofthe duck breeding- pair esti- 
mates by area (table E-24, p. 123) revealed 
that the 1963 total counts were up 7 percent 
from 1962, and 83 percent above the (1954. 
1962) 9-year average, In spite of a dry sea- 
son, it was apparent that sufficient nesting 
habitat was available to continue the year-to- 
year upward trend in breeding-pair numbers 
which Colorado is experiencing. 
Comparison of individual breeding ground 
estimates between 1962 and 1963 showed that 
the duck population in the San Luis Valley was 
20 percent below last year and 74 percent 
above the 9-year average, In the Yampa 
Valley ducks were 9 percent below last year 
36 
