12 
The 1978 duck production was well below that of 1977, 
which was also down from recent years, and it was well 
below the 10-year average. Ducks did not respond to an 
increase in available water areas with an expected in- 
crease in production. Mallards were down from the 
average, but not as much as other dabblers. Most of the 
dabbler decline was the result of a dramatic decline in 
blue-winged and cinnamon teal. Evidently, teal shifted 
to other locations during the 1977 drought and did not 
return during 1978. Redheads did not respond to im- 
proved water conditions with an increase in production; 
the same was true for canvasbacks. It would seem that 
the current bag and possession limits on these species are 
too liberal. Canada geese continue to do well in Wash- 
ington. 
California 
Data supplied by J. LeDonne, Frank Kozlick, B. Deuel, and 
D. Hinz 
California Department of Fish and Game 
Weather and Habitat Conditions 
Habitat conditions in northeastern California were 
much improved this year over 1977, which was the State's 
driest year on record. Conditions were fair and most of 
the normally stable water impoundments and marshes 
were once again holding water; however, some perma- 
nent and most of the temporary waterfowl habitat that 
was available in a good water year still lacked water and 
showed the effects from the drought years of 1976 and 
1977. With the high land values, native pasture and 
meadows that produced waterfowl! were being replaced 
with cereal crops and alfalfa. Also of great importance to 
the resource was the change in irrigation methods from a 
flood-type to overhead sprinkler systems. This method 
saves and uses water more efficiently; however, it al- 
lowed more marginal land to be brought into agriculture 
productions, which further reduced wetland habitat. 
The Central Valley received above normal amounts of 
rainfall and this, together with the runoff from the record 
snowpack in the Sierra Nevada Mountains, filled the 
State’s reservoirs and caused flooding in many valley 
areas. Similar to 1969, floodwater poured into the Tulare 
Basin areas inundating these lands. Thousands of ducks 
and coots remained to nest in these areas that were nor- 
mally dry farmland and not usually covered by the 
survey. This flooded area had water and weather condi- 
tions ideal for botulism, which predictably started in 
June. As a result, much of the duck production was nulli- 
fied with disease losses. The Central Valley is mostly com- 
posed of artificial and regulated water impoundments 
such as rice fields, grasslands, and pastures. In 1978 with 
good water conditions, birds scattered out to nest in a va- 
riety of other temporary habitat. Rice field preparation 
was 2 weeks to a month behind schedule, due mainly to a 
wet spring, which kept equipment out of the fields. How- 
ever, rice crop production increased to 1,000,350 ha, 
which represented a 27 % increase from 1977. 
Farm ponds, stock tanks, and other small wetland 
areas scattered over the entire State and not covered by 
this survey, were once again producing some ducks after 2 
dry vears. This would account for the slight decrease in 
breeding pairs and the fall population of ducks shown for 
the survey transects. 
Breeding Populations and Production Indices 
(Tables B-15 to B-21) 
The breeding ground survey for 1978 was conducted in 
essentially the same manner as in previous years, con- 
sisting of complete aerial coverage of the “Great Basin” 
section in northeastern California and aerial transects in 
the Sacramento Valley, San Joaquin Valley, and Bay 
Area. On the Klamath Basin National Wildlife Refuge, 
ground counts were made by refuge personnel and 
supplemented with aerial survey work. The survey flights 
in the Central Valley were conducted 17-19 May, 
whereas northeastern California was surveyed from 5 to 
9 June 1978. 
The accumulated data indicated nesting pairs of 
Canada geese increased 20% but there was no change in 
the fall population index. Total ducks showed a decrease 
of 7% in nesting pairs, and the fall population index of 
coots was down 64%. 
Colorado 
Data supplied by Michael R. Szymezak and Steven F. Steinert 
Colorado Division of Wildlife 
Weather and Habitat Conditions 
In general, water conditions for duck production were 
much better in 1978 than in 1977. Conditions in the San 
Luis Valley continued to decline because of a combi- 
nation’of dry weather and an increase in circular sprink- 
ling from wells as opposed to flood irrigation. Water 
conditions in North Park were below average, as a cool, 
wet spring retarded the initiation of the irrigation season. 
However, conditions in the South Platte and Cache la 
Poudre Vallevs were excellent: all ponds and ditches were 
full of water. In the Yampa Valley a heavy snowpack re- 
sulted in some temporary ponds retaining water into the 
nesting season, but the permanent ponds that were de- 
pendent upon irrigation water were low because of the 
delay in irrigation. 
Conditions for Canada goose production were excellent 
along the rivers in northwest Colorado. Normal water 
flows resulted in the average number of usable islands 
throughout the nesting season. High water levels were not 
experienced until after the peak of hatch. In north central 
Colorado reservoir water levels were higher than in 1977. 
However, a 67-cm snowfall near the peak of hatch defi- 
nitely reduced production from expected estimates. 
Breeding Populations and Production 
(Tables B-22 to B-30) 
The estimated number of duck breeding pairs were 
very similar to 1976 levels and 22% above the long-term 
average (Table B-22). The number of pairs in the San 
Luis Valley remained stable in spite of a valley-wide de- 
cline in habitat conditions. A decrease in the North Park 
duck population was more than compensated for by large 
increases in the South Platte and Cache la Poudre 
Valleys. Mallards made up 29% of the breeding pair 
population — an increase over the 1976 level, but still far 
below the long-term average (Table B-23). The mallards 
were followed in descending order of abundance by gad- 
wall, green-winged, blue-winged, and cinnamon teal 
(each composing more than 10% of the population). 
The post-nesting season population of Canada geese on 
trend areas in northwestern Colorado was projected to be 
1,710 birds in 1978 (Table B-24) and was down 9% from 
1977 but 7% above the 1967-77 average (Table B-25). 
Gosling production (773) was 13% above the 1977 level 
and 40% above the 1966-77 average (Table B-26). 
Results of the 1978 production survey in north central 
Colorado are presented by individual area (Table B-27). 
Gosling production in north central Colorado was down 
20% from 1977 and 21% from the 1969-77 average 
(Table B-28). Production declined in all trend areas 
except Boulder and Loveland. The number of adults ob- 
served was up 20% from 1977 levels but still down 6% 
from the 1969-77 average (Table B-28a). 
The aerial survey of breeding Canada geese in west 
central Colorado was flown on 20 April 1978. The results 
are presented in Table B-29 and compared with 1977 fig- 
ures in Table B-30. The 1977 survey was conducted on 
9 May. In spite of the variation in survey dates between 
vears, the presence of more single geese during the earlier 
1978 survey probably indicated an increase in the number 
of active breeding pairs. 
Nebraska 
Data supplied by John T. Sweet 
Nebraska Game and Parks Commission 
Weather and Habitat Conditions 
In Nebraska, spring temperatures were generally low 
until mid-May, but periods of above normal tempera- 
tures occurred during June and July. Drought conditions 
were relieved in the northern and northeastern Sandhills 
and Rainbasin production areas by near average level 
rainfall. The central and southwestern areas of the Sand- 
hills showed some improvement but still remained rela- 
tively dry. Many water areas were drying rapidly by the 
13 
first part of July. Sandhills Mav water index was 38% 
above that of 1977. and total water areas increased by 
10% from 1977 in the July survey. 
Breeding Populations and Production 
(Tables B-31 and B-32) 
The 1978 calculated breeding duck index for the Sand- 
hills production area was 126,006 birds, which repre- 
sented an overall increase of 45% compared with 1976 
(last vear of aerial surveys) population indices. Of the 10 
species identified during the counts, only the ruddy duck 
(-97% ) failed to increase over 1976 population levels. 
Ground route transects were driven through the Sand- 
hills production area during 11-14 July 1978 toestablish a 
production index. A total of 41 broods with 204 ducklings 
were Observed on transect. The average brood size of 4.98 
(Table B-32), all species combined, was 1.47 ducklings 
less than that of 1977. The number of broods sighted on 
transect was 273% above 1977, whereas the number of 
ducklings observed was 187% above 1977 levels. 
Wisconsin 
Data supplied by Dave Evenson, Bruce Moss, and Jerry Bartlet 
Wisconsin Department of Natural Resources 
Habitat Conditions 
Data gathered from the aerial survey on wetland 
abundance and distribution indicated a 114% increase of 
wetlands per 2.95 km? (Table B-33) from 1977. Wetland 
types IV, V, streams, and ditches were the areas most 
used (71% of all wetland types) by Wisconsin’s breeding 
waterfowl (Table B-34). 
Breeding Populations (Table B-35) 
Total breeding ducks in Wisconsin increased 4% from 
1977 to 1978; mallards increased 34% and blue-winged 
teal decreased 25%. Total ducks increased 22% in the 
southeast-central region, increased 4% in the northern 
low region, and decreased 14% in the northern high 
region. 
Although mallard populations experienced a statewide 
increase of 34% compared with 1977, it should be 
emphasized that 1977 had the lowest population of mal- 
lards since the survey began in 1973. The current mallard 
population in Wisconsin was still 7% below the 5-year 
mean for 1973-77. Statewide populations of blue-winged 
teal declined for the third consecutive year. The current 
population of blue-winged teal was 43% below the 5-year 
mean for 1973-77. 
Regional population trends for breeding mallards in- 
creased slightly in all regions. Blue-winged teal popu- 
lations increased slightly in the southeast central region 
and declined in the two northern regions. 

