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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123, No. 1, March 2011 
irruptions in contrast to a seemingly determinate 
migration strategy as seen in virtually all other 
passerines. 
ACKNOWLEDGMENTS 
We thank the Tyler and Hynes families for use of their 
homes as recording sites. We thank the Biology Department 
at Bates College for funding all travel expenses for M. L. 
Watson. We also thank W. R. Evans. M. O'Brien, and D. A. 
Sibley for reviewing our recorded flight calls. 
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The Wilson Journal of Ornithology 123 ( 1 ): 164-167, 2011 
Onemation of Sap Wells Excavated by Yellow-bellied Sapsuckers 
Ashley M. Long 1 
selechon o^f 1 tem P erature may influe 
f §mg SUeS by or 8 a m sms that use sap 
S0UrCe ' 1 6Xamined the s P atla l orienta 
of sap wells excavated by Yellow-bellied Sapsucl 
ff 'T CU J Varius) on P ine (Pinus spp. n = 
in eastern Kansas. Sap wells were oriented toward 
southwest (d = 246.04. y = 6x46 . P = a00 4 T u n 
in previous studies. Benefits of southwesterly sap well 
orientation may include avoidance of high winds while 
foraging and increased flow of sap on the sides of trees 
warmed by afternoon light. Received 2 November 2009. 
Accepted 25 October 2010. 
' Department of Biological Sciences, 
University, Emporia, KS, 66801, USA; 
e-mail: ashley_long@tamu.edu 
Emporia 
State 
The Yellow-bellied Sapsucker (Sphyrapicus 
varius) is a small-medium, migratory woodpecker 
(21—22 cm) that breeds throughout Canada and 
portions of the northern United States and 
