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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123, No. 2, June 2011 
Used {n = 53) 
Unused (n = 47) 
FIG. 2. Mean species richness, diversity index, bird abundance, and number of species of conservation concern 
If?ni a l. PO, ? t COUntS conductcd in areas llsc d and unused by Cerulean Warblers in northern Alabama during the 2005 
and 2006 breeding seasons. All values were significantly higher (P < 0.01) at used locations. Error bars are + SE. 
Inc. 2006). Means ± standard error (SE) are pre¬ 
sented unless noted elsewhere. 
RESULTS 
Bird Surveys .—Approximately 50 Cerulean 
Warbler males were detected in northern Alabama 
during each of the 2005 and 2006 breeding 
seasons. Cerulean Warblers were found only in 
Jackson County along Larkin Fork and Hurricane 
and Mill creeks in Walls of Jericho, and Lawrence 
County in Bankhead National Forest along 
Borden, Flannigan. and Horse creeks. No Cerule* 
an Warblers were encountered at unused points or 
during additional target searches throughout 
Jackson County or BNF. Walls of Jericho had 
the highest number of detections with 20 males 
followed by 15 territorial males in Bankhead 
National Forest and Larkin Fork. 
Bird species richness (r = 4.91. df = 98 P 
0.01), abundance (/ = 3.85, df = 98 P < 0 0 
diversity </ = 4.99, df - 98, P < 0.01). r 
conservation concern values {t = 9.06. df = 1 
p < 0.01) were significantly higher in an 
where Cerulean Warblers were detected compai 
o areas where they were not found (Fig ~>) \ 
detected no difference in abundance of Brow 
headed Cowbird (/ = 1.06, df - 98. P < 0 > 
Amencan Crow (t = -0.63, df =98 P < 0 5 
Blue Jay {t = -1.01, df = 98. P < 0.31), or Red- 
bellied Woodpecker (t = 0.85, df = 98 ,P< 0.40) 
between used and unused locations. 
Avian Community Associations— The propor¬ 
tion of variance explained by the DCA ordination 
was 23.7% with the first two axes accounting for 
greater than half of the variability (13.5%). 
Species most closely associated with Cerulean 
Warblers were Kentucky Warbler ( Oporomis 
fonnosus). Northern Parula {Parula americam). 
Acadian Flycatcher ( Empnionax virescens). Blue¬ 
winged Warbler ( Vermivora cyanoptera ), Louisi¬ 
ana Watedbrush {Parkesia motacilia ), American 
Redstart (Setophuga ruticilla). Belted Kingfisher 
{Megaceryle alcyon), and Indigo Bunting ( Pus- 
serinu cyanea ) (Fig. 3). Bird community associ¬ 
ations revealed by the DCA suggested Axis 1 
represented a gradient from xeric upland to mesic 
bottomlands, while Axis 2 distinguished interior 
deciduous forest from edge and mixed forest 
habitat. 
Microhabitat Characteristics. —Used plots. 
When compared to unused habitat, had signifi¬ 
cantly fewer live trees 2=3 cm DBH (t = -4.01. 
dl = 97, P < 0.01. Table 1). higher ratio of basal 
area to number of stems (t = 3.56. df = 97. P < 
0.01), greater percentage of deciduous basal area 
(2 = -4.5, df =97 , P C 0.01), taller lower. 
