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THE WILSON JOURNAL OF ORNITHOLOGY • Voi 123. No. 3. September 2011 
FIG. I. Transect locations, denoted by black circles, along the northern Lake Huron shoreline. 
short- or long-distance migrant (Gauthreaux 
1991), and omitted resident species from the 
analysis. Migrants that breed north of the study 
area (northern breeders. Brewer et al. 1991), 
including (Philadelphia Vireo (Vireo philadelphi- 
cus), Gray-cheeked Thrush (Catharus minimus), 
Tennessee Warbler (Oreothlypis peregrina), 
Orange-crowned Warbler (O. celata). Cape May 
Warbler (Dendroiea tigrina ), Palm Warbler (1). 
palmarum ), Bay-breasted Warbler (D. castanea), 
Blackpoll Warbler (D. striata). Connecticut War¬ 
bler (Oporornis agilis), Wilson’s Warbler (Wilso- 
nia pusilla), and White-crowned Sparrow (Zono- 
trichia leucophrys), were analyzed independently 
from long-distance and short-distance migrants 
known to breed in the study area. 
We were not able to distinguish individuals 
arriving to breed from those passing through our 
site en route to a more northerly or southerly 
migratory destination. This may confound interpre¬ 
tation ot spatial distribution during both spring and 
tall migration. A comparison of banding records 
from spring migration to the breeding season for six 
species, Magnolia Warbler (Dendroiea magnolia). 
Yellow-rumped Warbler (D. coronata). Black- 
throated Green Warbler, Blackburnian Warbler 
(/>. fused). Black-and-white Warbler I Mnioiilta 
varia ). and American Redstart captured in shoreline 
habitat within the same study area indicated that 
many more birds passed through the area than 
subsequently stayed to breed (R. J. Smith and F. R- 
Moore, unpubl. data). Local breeders composed 
only a small percentage of the total captures during 
spring migration, and it is likely the spatial patterns 
observed in this group of species are valid. 
We described forest composition at each point- 
count station using point-quarter sampling (Cot- 
tam and Curtis 1956). Description of the under¬ 
story or shrub layer (shrubs were defined as 
<0.5 m tall and <2.5 cm diameter at breast 
height) was by counting all woody stems within a 
10-m radius circular plot. 
We tracked the phenological development of 
spring leaf-out and fall leaf-drop to estimate and 
