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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 124. No. 3. September 2012 
TABLE 4. Number of observations of male Cerulean Warblers (20 on Hart Ridge, 9 on Snake Ridge) by activity (sing, 
forage, all activities combined) and tree species in Wetzel County. West Virginia. May-June 2005. 
Hart Ridge 
Snake Ridge 
All 
All 
Tree species 
Sing 
Forage 
n 
% 
Sing 
Forage 
n 
* 
Ash. White/Green (. Fraxinus spp.)" 
48 
9 
80 
10.5 
10 
1 
23 
6.8 
Black Cherry ( Primus serotinaf 
86 
27 
160 
21.0 
0 
Black Locust ( Robinia pseudoaeacidf 
66 
17 
128 
16.8 
0 
Black Walnut (JugIans nigraf 
45 
9 
82 
10.8 
2 
4 
1.2 
Hickory (Carya Spp.)" 
9 
2 
55 
7.2 
23 
3 
47 
14.0 
Mockcrnut Hickory (C. tomentosa) 
2 
1 
6 . 
0 
Pignut Hickory (C. glabra) 
1 
3 
3 
2 
5 
Shagbark Hickory (C. ovata) 
1 
0 
Unknown spp. 
6 
1 
45 
20 
1 
42 
Oak (Quercias spp.) 
Chestnut Oak (0. prinus) 
0 
49 
1 
57 
17.0 
Northern Red/Black Oak (Q. rubra/ 
19 
1 
42 
5.5 
26 
1 
55 
16.4 
vatutina)" 
Scarlet Oak ( Q. coccinea) 
0 
3 
1 
17 
5.1 
White Oak (Q. alba ) 
0 
3 
12 
3.6 
Unknown spp. 
0 
9 
1 
12 
3.6 
Maple ( Acer spp.) 
Red Maple (A. ruhruni)" 
16 
1 
33 
4.3 
5 
6 
1.8 
Sugar Maple (A. saccluirrum)" 
33 
10 
84 
11.0 
5 
1 
28 
8.3 
Unknown spp. 
0 
2 
0.6 
Tulip Poplar (Liriodeiulron tuHpiferaY 
29 
15 
80 
10.5 
17 
2 
30 
8.9 
American Beech {Tagus grandifolia) 
0 
I 
1 
0.3 
Apple l \lalus sylvestris) 
1 
2 
0.3 
0 
Basswood (Tilia ament-ana) 
5 
8 
l.l 
7 
14 
4.2 
Black Gum (Nyssa ss-lvatica) 
0 
1 
1 
2 
0.6 
Cucumber Magnolia ( Magnolia acuminata) 
1 
3 
0.4 
6 
4 
17 
5.1 
Elm (Ulmus spp.) 
1 
0.1 
2 
2 
0.6 
Redbud ( Cards canadensis) 
1 
0.1 
0 
Sassafras ( Sassafras albidurn) 
1 
1 
2 
0.3 
1 
0.3 
Sourwood (Oxydcndntm urboreum) 
0 
6 
6 
1.8 
Used in Chi-square analysis comparing tree use for singing vs. foraging on Hart Ridge. 
the upper-canopy where advertisement behavior 
tor mating or territory defense would be impor¬ 
tant. Conversely, foraging, perching, and preening 
occurred less than expected in the upper-canopy, 
perhaps in an attempt to remain inconspicuous 
while performing these activities. These three 
behaviors occurred most often in the lower- 
canopy and mid-canopy strata where individi 
would be less vulnerable lo aerial predation. 
Cerulean Warblers spent the majority of t 
time engaged in singing activities and sing 
occurred more frequently than expected wii 
core areas of territories, similar to that reportec 
Barg et al. (2006). Cerulean Warbler territo 
are often clustered fHamel 2000a, Roth and Isl 
007) and most territories mapped on our st. 
sites had multiple neighbors. Males frequently 
moved to a new singing location to counter-sing 
in closer proximity to an adjacent male that 
approached a common territory boundary. This 
behavior was so pronounced for some individuals 
that edges of territory boundaries often over¬ 
lapped. Thus, core areas may serve as strategic 
locations for territorial defense among multiple 
neighbors especially where densities are high. 
Barg et al. (2006) reported higher song-f** 1 
densities within core areas and suggested core 
areas may be selected primarily for characteristics 
related to enhanced song projection. Our finding 
that males singing within core areas used the 
upper-canopy more than expected supports tfu's 
hypothesis because higher locations within core 
