GOOSE BREEDING GHOUSD SURVET In UTAH AWD IDAM - 1949 
G. Hortin Jensen and Noland F. Yelson 
Eetimation of the Canada goose breeding population in Great Salt Lake 
ralley has been a part of studies carried on during the pact few years. This 
ig B part of a larger study on a comparison of census methods. The coose 
population has been used as the subject material beeause considerable fe knoown 
of their flyway. 
Methoda 
The method used has been to sample a part of the nests to dstermine the 
average clutch and hatch eigee. 
localities. 
geese on the given breeding fround. 
Total brood counts are made of breeding 
These date are used to calculate the population of breeding 
4a gooee broode gang up, one cannot rely 
on counting of individual] breeds to determine the breeding paire. 
Instead, 
the total count of juvenile geese divided by the avernmge hatch, saeeuning 
little predation, givee an estimate of breeding palire- 
on juvenile geese In Utah. 
Fredation ia very low 
Thie same procedure has been followed on some 
areas eince 1946. By comparing the number of breeding paire from year to year 
we cau follow incresees or decreases in the population. 
This year we have 
need data from areas where only brood counte were available. 
Eatimation of 
breeding palrs wae done by weing the averngt hatch for Utah conditions, 
approximately four goslinge per clutch. 
Information 
The following is a summary of nesting conditions found on two Utah 
BT@Ag, 
for comparison. 

Those from the Piackfoot Reservoir in southeastern Idaho are given 

Rees Eece Egee not Eggs 
Hatched Batched Deserted 
Bear River (1946 558 an? (23.04) 46 ( 7.5%) 56 ( 9.56) 
(1947 BG? 948 (86.2%) a7 (10.0%) 32 { 3.78) 
(1948 SE] 770 (87.5%) 100 (11,34) 11 ¢ 1.2%) 
(1949 358 276 (81.4%) 52 (18.4%) to ( 3.24) 
Ogden Bay (1947 94 76 (81.0%} a pew of) 
(194g 58 az (74.0%) rete %) 
(1949 ag o7 (87.3%) 6.9%) st 5.58) 
Blackfoot (1946 207 og (48.0%) a2 (20,0%3 67 (32.0%) 
Reservoir {1947 757 257 (45.4%) 279 (43.2%) ( 6.4%) 
(1948 BAA 413 (74.0%) es (14,86) 63 (11. 2%} 
(1949 710 379 (53,4%) 225 (51.4%) 106 (15.2%) 
Average Clutch Average Batch 
Bear River (15946 4.90 ezen 4.10 eee 
(1947 5,20 4,50 
(1946 5.12 4.45 
(1949 6.00 4.13 
one 
