An Apparent Differential Migration of Cedar Waxwings 
in West-Central Illinois 
By H. DAVID BOHLEN 
Illinois State Museum 
Springfield, Illinois 62706 
The migration or appearance of Cedar Waxwings (Bombycilla 
cedrorum) has always seemed erratic, and some winter in areas where 
food is plentiful. For the past five years, I have kept daily records on the 
birds of central Illinois. An analysis of this data on the Cedar Waxwing 
was made because of an absence of these birds during midspring migration 
for the past three years (1972-74). It was found that a pattern emerged. An 
early migration started in either late January or February and lasted until 
March or early April. Then, after a lapse of more than a month, there was 
another influx in mid-may which lasted until early or mid-June. For exact 
dates, see table below. 
LAPSE OF DAYS 
BETWEEN EARLY 
YEAR EARLY MIGRATION & LATE MIGRATION 
LATE MIGRATION 
Arrival (1 at Moweaqua) 
1970 Departure (3 at Moweaqua) (1 near Moweaqua) 43 
1971 Arrival (30 at Decatur) (10 at Springfield) 
Departure (1 at Springfield) (3 at Springfield) 39 
1972 Arrival (250 in Mason Co.) (5 at Springfield) 
Departure ; (2 at Springfield) (2 at Bath) 35 
1973 Arrival : (4 in Mason Co.) (15 at Springfield) 
Departure d (8 at Springfield) (6 at Springfield) 68 
nee : , , 
1974 rrival Feb 9 (9 at Springfield)|May 18 (10 in Mason Co.) 1 
Departure |Mar. 7 (3 at Springfield)! Jun. 5 (10 in Sangamon Co.) 
The cause of this differential migration is unknown. In 1972 and 1973, 
I thought the second migration was connected with emergence of the 
13-year and \|7-year cicadas (Magicizada), and I observed waxwings feeding 
on them. However, in 1974 there was no emergence, but the same pattern 
of migration occurred; and, in checking my data, I found there was a sim- 
ilar pattern in 1970 and 1971. During the second migration of 1974 the wax- 
wings were observed in mulberry trees (Morus) on several occasions; how- 
ever, during this period the fruit was not ready, but the waxwings could 
have been feeding on other portions of the tree. 
The differential migrations of this monotypyic species could be related 
to the following: (1) age groups, (2) sex groups, (3) a near migrant group, 
and a more southern migrant group, and (4) an eastern migrant group and 
a more western migrant group. Banding would probably be the best way 
to investigate this aspect of the problem. Any Cedar Waxwings nesting in 
west-central Illinois would be associated with the second migrational group. 
The differential migration may be confined to west-central Illinois 
(because of geography, habitat, etc.), since extensive daily lists from east- 
central Illinois in 1966 show that Cedar Waxwing migration on that side 
of the state was a steady process which lasted from February 7 to June 14 
Maybe it would be better to examine why there are no Cedar Waxwings 
from mid-April to mid-May in west-central Illinois. This could be due to 
lack of available food or just geographical phenomenon. 
It will take further study to determine if this is truly a differential 
migration or if my observations are biased. Others should examine this 
situation in their sections of the state. 
