Production Indexes 
Production of Canada geese in Utah is 
measured by brood counts. Thesecountsare 
made both by aerial and ground methods, 
Ground counts are made on management areas 
and on various lakes and reservoirs through 
the central portion of the State. Aerial counts 
are made in Rich and Cache counties in 
northern Utah. 
A significant increase in the number of 
broods and in goslings produced was noted 
throughout the areas censused, In 1962, a 
total of 737 broods containing 3,559 young 
were counted. Comparing these same areas 
in 1963, it was found that 809 broods were 
produced which contained 3,938 young. This 
is an increase of approximately 10 percent 
in the number of broods and 11] percent in 
the number of young from 1962, Canada goose 
production data are contained in table F-14 
(p. 143) of this report. 
IDAHO 
Data supplied by Elwood G, Bizeau 
Idaho Fish and Game Department 
Weather and Habitat Conditions 
Foltewing the driest fall and winter in 
recent years, Idaho received copious amounts 
of moisture beginning in late March and 
continuing through June. Precipitation during 
June over most of southern Idaho was more 
than 200 percent above average (U.S, Weather 
Bureau records). Irrigationreservoirs were 
at or near capacity with ample water assured 
for the waterfowl production season, 
With extremely mild weather prevailing, 
the spring movement of waterfowl had no 
sharp peak period. Waterfowl dribbled 
through the State from March to May. The 
pintail concentration at Market Lake in 
eastern Idaho which normally occurs inearly 
April had no outstanding peak this year, 
Due to lack of snow and above-normal 
March temperatures, goose and mallard 
nesting throughout southern Idaho began 2 
weeks earlier than normal. 
Breeding Population Indexes 
Aerial trend counts were conducted on all 
major goose nesting units for the ninth con- 
secutive year. 
25 
Total geese counted for all units combined 
were 37 percent above 1962 and 55 percent 
above the 1955-1962 average. Major in- 
creases were recorded for the Gray’s Lake 
and Dingle Marsh units (table E-13, p. 118). 
The only unit in the State which had a reduc- 
tion in breeding season numbers was the Mud 
Lake-Camas NWR area where flooding vir- 
tually wiped out production last year. 
Production Indexes 
Goose nesting surveys were conducted for 
the twelfth consecutive year. Results are 
based on number of goslings produced on 
identical areas surveyed in the same manner 
each year. For all six Idaho units combined, 
gosling production was up 24 percent from 
1962 and 36 percent above the long-term av- 
erage (table F-15, p. 143). 
The resident goose flocks of southwest 
Idaho had an outstanding year while the 
migratory flocks of southeast Idaho had mixed 
success, Production for the southwest area 
was 25 percent above 1962 and 50 percent 
above the long-term average. 
Increases were recorded for three of the 
four southeast Idaho units from 1962 to 1963 
but the only southeast unit which registered 
well above its long-term production norm was 
Blackfoot Reservoir. For the second con- 
secutive year, almost complete production 
failure was experienced at Mud Lake due to 
nest flooding caused by an adverse change in 
water storage practices. For the four south- 
east units combined, gosling numbers were up 
21 percent from 1962 and 12 percent above 
average. 
Duck production trend routes were censued 
in southcentral and southeast Idaho (table 
F-16, p. 144). Routes were run twice with 
all classes of broods counted on the early 
July run and only class 1 broods included for 
the late July run. 
Combined results for the two southeast 
Idaho routes indicated a 15 percent increase in 
duck production from 1962, The one south- 
central trend route yielded twice as many 
broods as any previous census year. 
Conclusions 
Numbers of geese counted by aerial census 
on Idaho goose breeding areas were up 37 
percent from 1962 and far above the long-term 
average. The important Gray’s Lake and 
Dingle Marsh units had major increases, 
