177 
Table IV. - Comparison of Waterfowl Production in the Cache la Poudre Valley, 
1950, 1951, 1952 and 1953 
mg apr ang eae a a te 
No. of No. of Average Number 
Year Broods Young Young per Brood 
1950 772 4,441 5.7 
1951 781 4,841 6.2 
1952 781 4,850 6.3 
1953 743 4,821 6.5 

Yampa River Valley 
The Yampa Valley is a long narrow floodplain and canyon extending from the 
headwaters of the Yampa River on the White River Plateau to its confluence with the 
Green River in northwest Colorado, a distance of 220 miles. The Valley varies from 
1/4-mile in width in the canyons to about 10 miles in width shortly after its emergence 
onto the floodplain proper west of Steamboat Springs. The water table along the entire 
non-canyon portion of the Valley is high, and development of sedge and cattail marsh 
extensive. This habitat, plus the oxbow, drain, and meandering stream areas, 
constitutes the waterfowl breeding grounds found in the region. 
Spring breeding duck populations were found to be about 15 percent less than in 
1952. This difference occurred mainly in the decrease of cinnamon, blue-winged, 
and green-winged teal pairs. Projection of figures obtained on the study areas 
revealed a total of 1,500 breeding-pairs, with a subsequent production of 1,030 broods, 
resulting in 69 percent breeding-pair success in the Yampa Valley in 1953. Average 
brood size in 1953 was 6,5, resulting in a total production of 6,690 young compared to 
8,670 for 1952 (Table V). This gives a decrease of 23 percent in duck production 
between the 2 years. 
Goose production, on the other hand, was significantly increased in the Yampa 
Valley this year. The production figures from 1952 indicate that 40 broods and 136 
young were produced, compared to the 1953 production of 90 broods and 540 young. 
Average brood size for Canada peese rose from 3.4 per brood in 1952 to 6.0 per 
brood in 1953, The increase in number of broods and birds per brood in the Yampa 
Valley in 1953 resulted in an increased goose production of 297 percent over that of 
1952. This increased production was largely the result of favorable conditions on the 
nesting grounds, of which moderate spring run-off on the Yampa River played a major 
part. However, the increase may reflect the decrease evident in adjoining areas such 
as Brown's Park and the Green River. 
