The Wilson Journal of Ornithology 124(4):728-736, 2012 
NESTING ECOLOGY OF SWAINSON’S WARBLERS IN A SOUTH 
CAROLINA BOTTOMLAND FOREST 
JENNIFER THOMPSON BISHOP,'" JOHN A. GERWIN.' AND RICHARD A. LANCIA' 
South ^Caroijnai^JSA 1“ » M* ** 
Clutches averaged ,± SE) 3.19 - (, t 0 e ‘ and ^ ,Vf, XtlTl ""'T7 ^ “ Nmodal distribu,ioD 
23-day cycle was 50% Lo<'isiic“exDosnn“'m ‘i t Hedglmgs per nest. 1 he Mayfield nest success estimate fora 
(Molothrus ater) nest parasitism next arc and SUCCesS hc m,1M i ' n P ac ' e ‘J by Brown-headed Cowbird 
and further from a swamp had the highest daily su^val'mleT^Vn 0 ^'^, ' '" purasi,ized nests ,hat were younger ioage 
Cowbirds with a 26% reduction in 8wain«nn- u/. ■ . n percent of nests were parasitized by Brown-headed 
brooding was observed in 21% of 2000 and 2001 slaLin^ 1,1 P roduc,ion - Mul,i P le 
the most common substrate used for nesting, although two-thirds of ih - n - , mes - such as - erecnbner (Simla* spp.), were 
* i8a,Uea) within a 5 ' m ^ius. Received ,8 December 2<m. Accepted w Zllor {Anm ‘ i,mria tec,a mik 
Southeastern United States bottomland forests 
are one of the most rapidly diminishing wetland 
ecosystems (Gosselink et al. 1990). Sixty-nine 
percent ol bottomland hardwood forests in the 
lower 48 states have been lost since European 
seulement (Cassehnk ;m d Lee 1989) including 
X0 /r within the Southeast (Turner et al. 1981) 
Bottomlands support some of the highest bird 
densities in the southeastern U.S. (Dickson 1978) 
and are m need of study and sound management.' 
Only two ot the live bottomland specialists 
tcmain: Swainson's Warbler (Limnothvlpis swain- 
■vomo (more accurately described as an understory- 
dependent species due to its use of Rhododendron 
thickets m the Appalachian Mountains) and 
kr° n om ry R Warb ' er «>-) 'As- 
Kins _000, Benson and Bednarz 2010) The 
iemaining three specialists: Carolina Parakeet 
{Connraps,s carolinensis ), Ivory-billed Wood- 
princi P“ lis and Bachman’s 
exfin fi T™ bachma " i » are extinct or near 
extinction as the result of habitat loss and other 
factors (Askins 2000). Current assessments by 
Partners in Flight (Panjabi et al. 2005) indicate 
“ ns in - s “ 
sssssre » D r nmM 2 ”'- 
NC 27695. USA ^mvcrsuy, Box 7617. Raleigh. 
Jones Street, Ra'leU 1 NcTy^lT usa' Scienccs - 11 Wesl 
On.vers,ty. Box 7646. Raleigh. NC 27695. w S A 
Corrcsponding author; e-mait: bishop j@uni( , n .^' 
728 
Swainson s Warbler is a leaf-litter special!: 
that breeds in the southeastern U.S. and winters i 
the C aribbean Basin. Breeding habitat in bottom 
land hardwood forests of the Atlantic and Gul 
coastal plains and in high mountain riverine area 
ol the Appalachian Mountains is disjunct. Severa 
studies since Meanley’s (1971) seminal mono 
graph on Swainson's Warblers have shed eonsid 
viable light on this bird’s habitat preference anc 
breeding biology (Graves 2002, Henry 2004. 
Benson et al. 2010b). although gaps still exist, 
paiticularly in understanding of its breeding 
biology. This warbler's secretive nature, inhospi¬ 
table breeding areas, and inconspicuous nests 
have resulted in its classification as the most 
pooi |y understood of the migratory warblers 
(Brown and Dickson 1994. Graves 1996). 
Hus species a I Unity for early-successional 
habitat or disturbance gaps in primary forest 
(Carrie 1996. Graves 2001, Henry 2004."Benson 
ct al. 2009) could allow lor dual management ol 
Swainson’s Warblers while concomitantly ex- 
tracting timber through alternative forest manage¬ 
ment practices, (i.e., wildlife forestry), which 
maintain habitat heterogeneity and ecological 
integrity (Heltzel and Leberg 2006, Twedt and 
Somershoe 2009). Only a few studies have 
examined Swainson’s Warbler productivity in 
industrial forests (Carrie 1996. Peters et al. 
-0(b, Bassett-Touchell and Stouffer 2006). Most 
studies have been in non-industrial forests (Eddel- 
man et al. 1980. Thomas et al. 1996. Graves 2002. 
■Somershoe et aL 2003, Lanham and Miller 2006 . 
enson et al. 2009). which are typically subjected 
.° min ‘ mid harvesting when compared to more 
ntensively-managed private lands. Understanding 
