Vol. 21, No. 8 
Page 3 
Pheasant eggs were found in three prairie chicken nests this summer, two of 
which were destroyed by predators; one apparently hatched. Three other prairie 
chicken nests that contained intact but abandoned eggs (two involved clutches of 
14 incubated eggs each) were in close proximity to crowing territories of pheasant 
cocks. A total of 13 pheasant nests were found on the sanctuaries at Bogota this 
summer, the largest number to date. Clutch size for seven incubated pheasant 
nests averaged I 3.7 eggs and ranged from 10 to 18 eggs. 
Thus, nest numbers and reproductive performance of prairie chickens and 
pheasants at Bogota in 1978 did not reflect the severity of the previous winter. 
However, the number of quail nests (5) found this year was the lowest since 
1966. Only one ground nest of a mourning dove was found, also a record low. 
Meadowlarks, grasshopper sparrows, short-billed marsh wrens, dickcissels, field 
sparrows, and even red-winged blackbirds showed similar strong declines in 
numbers of nests. Cottontail rabbit nests (28), however, were the second 
highest on record. Small mammal (prairie vole and southern bog lemming) nests 
( 2 , 077 ) were about average in 1978 . 
Thus, although skunks and apparently pheasants were direct contributors 
to the low nest success of prairie chickens this summer, that-portion of the 
food base consisting of small birds was sharply reduced, thereby limiting prey 
opportunities for predators foraging on the sanctuaries. In previous years 
1 when nest success was low and the proportion of prairie chicken nests to nests 
of other ground nesters increased, nest success of prairie chickens also declined. 
