The Wilson Journal of Ornithology 124(2):354—361, 2012 
ENVIRONMENTAL FACTORS AFFECTING NEST-SITE SELECTION 
AND BREEDING SUCCESS OF THE WHITE STORK {CICONIA 
C/CONIA) IN WESTERN TURKEY 
ORTAC ONMU§,' 3 YILDIRIM AGAOGLU,' AND OR HAN GUL 1 
ABSTRACT. We investigated nest site selection and breeding success of White Storks (Ciconia ciconia) in relation lo 
geographical features, weather, and land use in western I'urkey. Locutions of nests in relation to altitude, distance to the 
nearest river and stream, slope, and aspect were examined between 2008 and 2010 in Sindirgi District. Population dynamic- 
of breeding White Storks were surveyed in the central town in 10X4. 1087. and between 1992 and 21110. WJuteStoib 
nested in only 17 of 74 settlements. Twenty-six of 46 nests were occupied in 2010 with a mean density of 1.72 heed® 
pairs/knr. Settlements with nests were significantly lower ix ± SD) in elevation (283.3 r 77 t vs 622.5 ± 230.7 m-an! 
closer to the nearest river (1.646.2 ± 1.004.5 vs. 4.101.7 ± 3.231.5 m) than settlements without nests. No signified 
difference was found between the mean aspects of the settlements and the distances to the nearest stream between iw.*w 
groups ol settlements. The number of breeding pairs and fledglings had a significantly decreasing trend througtiou; tk 
study period. The number of breeding pairs was positively correlated vs ith the annual total area of crop fields and itef/jv* 
com ated with the total atea ol Iruit production. The number of breeding pairs was positively correlated with to;al and 
maximum precipitation in April, but breeding success was negatively correlated with mean total precipitation and m a 
maximum precipitation during the breeding season. Received 12 September 2011. Accepted 26 December 2011. 
The White Stork (Ciconia ciconia) is a polytypic- 
species that breeds extensively in the Western 
Palearctic Region. This species breeds near open 
natural or extensively cultivated lowland, wet 
grassland or farmland, and high breeding densities 
occur along rivers with regularly flooded grass¬ 
lands (Cramp and Simmons 1977). 
The breeding success and productivity of White 
Storks have been studied for many years. 
Tsachalidis and Goutner (2002) found the growth 
rate ol White Stork fledglings depended on food 
provisioning rates, parental care, and diet. Tryja- 
nowski and Kuzniak (2002) reported population 
size and productivity of White Storks were 
strongly correlated with the density of common 
voles (Microtus arvcilis). Tryjanowski el al. 
(2005a) found that water level and livestock were 
correlated with productivity and numbers of 
breeding pairs. Similarly. Tortosa et al. (1995, 
2002) found that rubbish dumps positively 
influenced breeding, as well as wintering numbers 
of White Storks. There is little quantitative 
information on nest site selection of White Storks 
Carrascal et al. (1993) found that density of 
breeding pairs was negatively correlated with area 
ol woodland and scrub habitat, and positively 
f B ' ol0gy ’ Fuculf y of Science, Na 
History Museum Research and Application Center 
University, 35 100 Izmir, Turkey ' 
BaliI“ ri ^ r S k " ,ar "’ aCy - ° f Rcr-Nic. Sindi 
1 Corresponding a uthor; e . mail: o,,ac.„„ mus@ege . ed 
correlated with area of dry and wet grasslands. 
Similarly, Nowakowski (2003) found that While 
Storks commonly breed close to rivers, and there 
was a positive correlation between number of 
nestlings raised and the proportion of wel mea¬ 
dows. peat bogs, and water bodies. Few studies 
have examined the importance of other geograph¬ 
ical parameters in nest site selection by While 
Storks and information on nest site preferences 
has rarely been quantified. 
There is little standardized monitoring and few 
studies relating to the conservation of White 
Storks despite its high popularity in Turkey Mom 
studies are unpublished project reports or theses, 
which arc not available to the wider scieuriit- 
community. The wide range in estimates of 
breeding population size for White Storks in 
Turkey (15.000-35,000 pairs) also indicates j 
deficiency of appropriate data (BirdLife Inten¬ 
tional 2004). Local population surveys have been 
conducted over the Iasi two decades in TurlO 
but most are short term focusing on number 
breeding pairs and few collect data on nunrn-'f 1 
fledglings. 
We report on the population of White Sic - 
breeding in Sindirgi. western Turkey studied' ' 
19 consecutive breeding seasons between 
and 2010. This is the longest monitoring sl1 ' 
within the country. Our objectives were m. 
investigate the effects of altitude, slope, asp 6 ' 
and distance to nearest river and stream on ,R ‘ 
site selection of White Storks: and (2) invest^ 
the influence of environmental factors 11 
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