<< 
10 
driest noted in the nearly 30 years that these surveys have 
been flown. Nesting birds were confined to only those 
areas that are managed for wildlife and on those natural 
marshes and water impoundments that have permanent 
water supplies. Many of the normally stable water im- 
poundments and marshes that produce birds'in a normal 
runoff year were dry, and temporary waterfowl] habitat 
created in good years was nonexistent. With the increased 
land values in California, native pasture and meadow 
lands are being replaced with cereal crops and alfalfa. 
Irrigation methods are also changing from a flood type to 
overhead sprinklers, which further reduces wetland 
habitat. 
The Central Valley experienced the driest winter on 
record with rainfall about one-third normal. The only 
major storm came in early January. The spring migration 
was earlier than normal, probably because of the warm 
weather and poor habitat conditions on the wintering 
grounds. 
Breeding Population Indices (Tables B-17 through B-23) 
Survey flights in the Central Valley were conducted on 
18 and 19 May; northeastern California was flown from 3 
through 10 June. Comparable figures of nesting pairs of 
waterfowl indicate (1) nesting pairs of Canada geese 
increased 22% while an increase of 17% occurred in the 
fall population index; (2) ducks showed an increase of 
28 % in nesting pairs and a 23% increase was noted in the 
fall population index; and (3) nesting pairs and fall popu- 
lation index of coots were up 43%. 
Colorado 
Data supplied by Michael R. Szymczak 
and Steven F. Steinert 
Colorado Division of Wildlife 
Weather and Habitat Conditions 
A less than normal winter snowpack resulted in water 
conditions considered far below average for duck produc- 
tion. The San Luis Valley entered its fourth consecutive 
dry year. Only North Park and Brown’s Park approached 
average conditions. Extremely heavy rains in mid-May in 
the South Platte Valley produced local flooding and nest 
destruction. Reduced water flows in the Yampa and 
Little Snake rivers resulted in a reduced number of is- 
lands for goose nesting and increased predation of estab- 
lished nests. In north central Colorado many of the 
reservoirs were not occupied at a normal rate. In spite of 
mild weather in early spring, goose nesting chronology 
was later than normal throughout most of the State. 
Breeding Populations (Tables B-24 through B-29) 
This survey was conducted from 21 April to 30 June. A 
variety of mechanical failures compounded by unrealistic 
mathematical projections resulted in the decision not to 
compute duck breeding pair estimates for most of Colo- 
rado. Only two survey areas provided comparable data 
(Table B-24). In the Yampa Valley, the total duck 
breeding pair index was up 2% from 1976 but down 21 % 
from the long-term average. Brown’s Park showed an 
increase of 70% from 1976 but remained 12% below the 
long-term average. 
Results of the 1977 Canada goose production survey in 
north central Colorado are presented in Tables B-28 and 
B-29. Gosling production was down from 1975 levels in 
all trend areas except Denver. Total geese observed was 
down for the second consecutive year and was below the 
8-year average. 
Wisconsin 
Data supplied by Joe Haug and Bruce Moss 
Wisconsin Department of Natural Resources 
Weather and Habitat Conditions 
Drought conditions caused a 50% decrease in water- 
fowl use of types I through III wetlands. The number of 
these wetlands declined 54% since 1976. All wetland 
types combined were down 37% for 1977. 
Breeding Population and Production (Table B-31) 
Table B-31 indicates a 2% increase in total breeding 
ducks in Wisconsin from 1976 to 1977. Total ducks 
showed a 15% decline in the Southeast Central Region, a 
9% decline in the Northern Low, and a 65% increase in 
the Northern High Region. Mallard and blue-winged teal 
populations experienced statewide decreases of 19% and 
14%, respectively, in 1977. Mallard numbers are at an 
all-time low since the surveys were started in 1965. The 
South Central Region showed a 48 % decline in mallard 
and a 51% decline in blue-winged teal since 1976, 
whereas the Northern High Region showed an increase in 
both mallards (+ 35%) and blue-winged teal (+ 64%). 
The Northern Low Region also experienced increases in 
mallards (+ 48%) and blue-winged teal (+ 160%). 
Increases in mallard and blue-winged teal population 
in both the Northern High and Northern Low Regions of 
the State may have been the result of birds normally 
nesting in the Southeast Central Region moving to regions 
with more permanently available water. 
Waterfowl Harvest Surveys 
Data supplied by Samuel M. Carney, Michael F. Sorensen, and 
Elwood M. Martin 
U.S. Fish and Wildlife Service 
This report provides estimates of waterfowl hunting 
activity and harvest during the 1976 season and compares 

them with estimates for the 1975 season. Estimates for 
both years were derived from information obtained from 
three sources: (1) the Postal Service’s report of duck stamp 
sales, (2) the U. S. Fish and Wildlife Service’s Question- 
naire Survey of Waterfowl Hunters, and (3) the Service’s 
Waterfowl Parts Collection Survey. 
Procedures 
An explanation of procedures employed in estimating 
hunter harvest and activity may be found in Special 
Scientific Report — Wildlife No. 138. Similar sample 
selection, stratification procedures, and computations 
subsequently have been followed. Major adjustments to 
data include those for activity by hunters less than 16 
years old, who are not surveyed because they are not 
required to purchase duck stamps (Table C-1), and those 
used to compensate for memory and prestige biases 
(Table C-2). 
Administrative Reports 
Data in this report are based on final duck stamp sales 
information. In the Administrative Report Waterfowl 
Harvest and Hunter Activity in the United States during 
the 1976 Hunting Season” (31 May 1977), preliminary 
estimates based on duck stamp sales through the third 
quarter of fiscal year 1977 were made available for the 
annual waterfowl regulations meetings in early August 
1977. Age and sex composition are not included herein, 
but were presented in the Administrative Report Age 
and Sex Composition of Ducks and Geese Harvested in 
the 1976 Hunting Season in Comparison with Prior 
Years” (2 June 1977). 
Results 
Bias-adjusted estimates of the total U. S. harvest of 
ducks (by species), coots, and unretrieved kill are pre- 
sented in Table C-3. Similar estimates relating to geese 
are in Table C-4. Detailed State-level estimates of the 
duck, goose, and coot harvest, migratory waterfowl 
hunting-stamp sales, and hunter activity and success may 
be found in Tables C-5 through C-9. These results include 
hunter activity and harvest during regular and special 
seasons combined. Four States have a September teal 
season; the harvest and species composition during that 
season is also shown separately in Table C-10. Estimates 
are presented as derived to assure agreement between 
totals and their component parts. This does not imply 
precision to the last hunter, duck, or day. 
ll 
The following is a resume of 1976 hunter activity and 
harvest success by flyway, showing degree of change from 
gee Flyway. —Duck stamp sales totaled 435,932 
(-1%), and 2,090,148 ducks (+12%), 125,940 coots 
(-24%), and 379,633 geese (-4%) were harvested during 
2,893,085 hunter-days (+1%). Those persons buying 
duck stamps for hunting average 6.6 days afield (+ 3%) 
and retrieved an average of 4.8 ducks (+ 14%) and 0.9 
goose (-2%) each. Estimates for the Atlantic Flyway are 
in Table C-5. 
gp eile Flyway. — Duck stamp sales totaled 854,924 
(-7 %), and 6,068,492 ducks (-8 % ), 598,709 coots (—7 %o , 
and 463,866 geese (-10%) were harvested during 
6,374,194 hunter-days (-11%). Those persons buying 
duck stamps for hunting averaged 7.1 days afield (-4%) 
and retrieved an average of 7.0 ducks (-l %) and 0.5 
goose (-3%) each. Estimates for the Mississippi Flyway 
rded in Table C-6. 
Neate Flyway. —Duck stamp sales totaled 429,661 
(no change) and 2,769,418 ducks (-6%), 60,625 ats 
(-30%), and 463,092 geese (-21%) were harvest 
during 3,012,036 hunter-days (-6%). Those SOT 
buying duck stamps for hunting averaged 6.6 days afie : 
(-5%) and retrieved an average of 6.2 ducks (-5%) an 
1.1 geese (-20 %) each. Estimates for the Central Flyway 
rded in Table C-7. 
Pacific Flyway. —Duck stamp sales totaled 388,340 
(-3%), and 4,152,787 ducks (+3%), 143,286 wen 
(-24%), and 371,682 geese (+16%) were harvest 
during 2,937,816 hunter-days (-5%). Those pr 
buying duck stamps for hunting averaged 7.1 days afie : 
(-2%) and retrieved an average of 10.4 ducks (+ 6%) an 
0.9 goose (+ 19%) each. Estimates for the Pacific Flyway 
ed in Table C-8. 
ee ae stamp sales totaled 18,455 (+13%), 
and 109,909 ducks (+56%), 1,105 coots (+ 34%), and 
13,979 geese (+21%) were harvested during 89,817 
hunter-days (+ 44%). Those persons buying duck stamps 
for hunting averaged 4.5 days afield (+ 20%) and re- 
trieved an average of 5.7 ducks (+30%) and 0.7 goose 
(+1%) each. Estimates for Alaska are recorded in Table 
: ae States. —Duck stamp sales totaled 2,127,312 
(-4%), and 15,190,754 ducks (-2%), 929,665 sbae 
(-14%), and 1,692,252 geese (-7%) were harvest 
during 15,306,948 hunter-days (-7%). Those asi 
buying duck stamps for hunting averaged 6.9 days afie F 
(-3%) and retrieved an average of 7.0 ducks (+2%) an 
0.8 goose (-4%) each. Estimates for the United States are 
recorded in Table C-9. 
