Wintering site selection is a major decision in a bird's annual life cycle since conditions experienced by individuals within a wintering site can influence individual fitness and ultimately ...population dynamics. If individuals show strong fidelity to specific sites, annual environmental effects can be reinforced. In this study we analyse winter resightings of ringed Dalmatian pelicans, collected during a 35-year-long ringing survey, to identify winter movement patterns of Dalmatian pelicans, assess the level of site fidelity both within and among consecutive wintering events and examine environmental factors that may contribute to an individual's decision to move towards a specific site during the winter period. Our results showed that the decision of Dalmatian pelicans to move towards a specific site was mainly driven by the site's size and temperature conditions. Larger wetlands can provide birds with higher resource abundance and offer more opportunities to exploit optimal roosting and feeding habitats, whereas wetlands that do not freeze during the winter are a definite requirement. Wintering movements were more likely to occur at short distances from a bird's natal colony, whereas it was uncommon for birds born in wetlands located in the Adriatic and Ionian coast to move eastwards during the winter, suggesting a level of spatial substructure. Furthermore, we showed that the species exhibits very strong within-year and among-year wintering site fidelity, with birds moving less during the winter, whereas juvenile birds travel greater distances than the rest of the age classes examined. Our conclusions could guide an effective approach to site-based conservation management at key wintering sites.
We investigated the effects of threats on breeding waterbirds in the Gediz Delta, Turkey. Breeding Bird Surveys were conducted in 2002 and 2006. The survey area comprised 305 UTM grids of 1 × 1 km2. ...Populations and distributions of breeding birds were compared between 2002 and 2006 for the UTM grids under threat and without any threat using paired samples t-test, Wilcoxon signed-rank test, and GIS. Urbanization, industrialization, pollution, overgrazing, disturbance, and illegal reed cutting and burning were identified in 151 (49.5%) of 305 grids in 2002. The mean total number of breeding birds per UTM grid slightly decreased in areas under threat, but significantly increased (P < 0.05) in areas without threat. The mean total number of breeding waterbirds significantly decreased (P < 0.05) in both the grids under and without threat. Out of 30 waterbirds breeding in grids under threat, 23 shifted their breeding locations. The total number of breeding pairs of 9 waterbirds decreased, 7 species increased, and 6 species were stable. The maximum breeding code of 6, maximum number of breeding pairs of 11, total number of observed birds of 11, and frequency of occurrence of 15 species significantly decreased in UTM grids under threat. Threats have significantly affected (P < 0.05) the breeding populations of bird species even in a short period of 4 years.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Dalmatian pelican (DP) Pelecanus crispus and the great white pelican (GWP) Pelecanus onocrotalus are listed as ‘Vulnerable’ and ‘Least Concern’, respectively, in the IUCN Red List. We present an ...updated estimation of the Black Sea/Mediterranean flyway population status of both species, based on data provided by experts working in all 7 countries of the region where pelicans breed and/or overwinter, who came together at the 1st Workshop on Pelican Research and Conservation in Prespa, Greece. The DP breeding population in the Black Sea and Mediterranean countries increased from 1730-2105 pairs in the years 2000-2010 to 2154-2437 pairs in 2011-2012. Approximately 40% of the Palaearctic breeding population of GWP occurred in Southeast Europe and Turkey. In 2011-2012 the GWP population in this region was estimated to be 4702-5175 pairs, and has remained more or less stable during the last decade. Although all the breeding sites for both species are in protected areas, disturbance at nesting places was considered to be the main threat. Direct persecution and electric power lines still cause occasional problems. In deltaic lagoons, erosion and inundation of nesting sites cause breeding failures in DPs, while in inland wetlands large water level fluctuations are a widespread problem. Decrease of fish stocks is a threat, especially in coastal areas. Many stop-over wetlands along GWP migration routes between Southeast Europe and Africa have been seriously degraded or have disappeared, resulting in serious implications for their populations. Conservation needs are listed, but further research is recommended for both species.
Metapopulation conservation should rely on a flyway approach aiming at assessing the spatial range of metapopulations by estimating the level of exchanges among local populations. In the western ...Mediterranean, Greater Flamingos have been shown to constitute a metapopulation with natal and breeding dispersal among colonies. In this paper, we examine whether this metapopulation reaches Turkey using a band-resighting study. Our results are the first evidence of natal and breeding dispersal from the western Mediterranean to Turkey, and suggest that the Gediz Delta, one of the two Turkish breeding colonies, can play a significant role in the recruitment of flamingos from the western Mediterranean. In 2003 and 2004, breeders of western Mediterranean origin accounted for more than 1.2 and 1.9% of the estimated breeding population of the Gediz Delta, respectively. Our observations also indicate that the western Mediterranean and Southwest Asia may constitute two sets of populations, which overlap in Turkey. Finally, the resightings of flamingos banded in Turkey show that post-fledging dispersal from Turkey reaches both the eastern and western Mediterranean wetlands. Future data on the natal and breeding dispersal of flamingos born in Turkey could clarify further the connection between Turkey and the western Mediterranean metapopulation.
•POP concentrations represent a decreasing trend over time.•Venous blood represents promising biomonitor for internal PCB concentrations.•Enzyme activities correlate with the liver concentrations of ...several OCPs.•Egg DDE levels are below the threshold for the risk of hatch and reproductive success.
Three main groups of persistent organic pollutants (POPs); namely organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs) were quantified in water and sediment samples, as well as in various invasive and non-invasive samples from waterbirds in the Büyük Menderes River (BMR). Liver and muscle tissues, blood, and preen gland oil samples of yellow-legged gull (Larus michahellis) and Euroasian coot (Fulica atra) were collected both from the origin (Işıklı Lake) and the estuary (Söke) of the river, blood and preen gland oil samples of grey heron (Ardea cinerea) and pelican (Pelecanus crispus) were collected from the estuary only. In addition, non-hatched eggs from several above species and Mediterranean gull (Larus melanocephalus), in either station were collected. In all samples, POP contamination was measured and the potential usefulness of those invasive and non-invasive sampling for biomonitoring was evaluated. Activities of antioxidant enzymes were measured as potential indicators of POP exposure and of changes in the cellular defence. Venous blood proved to be a promising biomonitor for the concentrations in liver and muscle, especially for PCBs. Activities of antioxidant enzymes were correlated with the liver concentrations of several OCP congeners. The measured egg DDE concentrations were below the established threshold concentrations for the risk of hatch and reproductive success.
Between 3 and 18 May, 2008, the status and distribution of breeding birds in Küçük Menderes Delta on the coast of the Aegean Sea in western Turkey was investigated. The 49 km2 large study area was ...divided into 49 1 × 1 km UTM squares. In all squares, 2-3 point counts, i.e. a total of 139 counts, were conducted. From a total of 54 bird species for which breeding evidence was obtained, 19 species (35%) were classified as possible breeding and 23 (43%) as probably breeding birds, while for 12 species (22%) breeding was confirmed. The current distribution of all breeding species is presented in maps. Crested Lark Galerida cristata, Cetti's Warbler Cettia cetti, House Sparrow Passer domesticus and Olivaceous Warbler Hippolais pallida were found in > 50% of all squares. More than 10 breeding species were found in squares containing different aquatic and seasonally flooded habitats along the shore-line of the Aegean Sea and in the surroundings of brackish and freshwater lakes, while in many squares, which contain large portions of agriculturally used land and salt mud-flats, less than 10 breeding species were recorded. Low numbers of breeding waterbirds in the Delta are attributed to the burning of reedbeds during the nesting season and human disturbances, like recreation activities and illegal bird shooting.
Razširjenost gnezdilk v delti Küçük Menderes (zahodna Turčija)
The Dalmatian Pelican, Pelecanus crispus (Bruch, 1832), used to be a widespread breeding species in Turkey in the past. Until the 1990s, approximately 473-763 pairs were breeding at 20-25 sites. Of ...these, 53-59% have been lost due to drainage of wetlands, 17-19% due to direct persecution, 16-22% due to both drainage and persecution, and 6-8% due to water level increase. Currently there are only five active breeding colonies: Gediz Delta, Manyas Lake, Bueyuek Menderes Delta, Aktas Lake and Isikli Lake. The colony at Isikli Lake was discovered in 2010 and comprises 6 pairs. Since 2000, the total breeding population of Dalmatian Pelicans increased moderately from 220-250 to 277-341 pairs. Likewise, the wintering population has also increased from 352 up to 2,344 individuals, which seems to be linked with the increase in the breeding population in the region. Nevertheless, the population size still renders the species susceptible to the risks affecting small populations.
The Greater Flamingo Phoenicopterus roseus is a waterbird commonly found in saline and brackish lagoons throughout the Mediterranean Region. We have gathered existing data on Greater Flamingos in ...Turkey and carried out field surveys to present the most up to date information on wintering (1999–2014) and breeding (1969– 2014). The wintering population of flamingos shows an increasing trend with 54,947±20,794 individuals mainly concentrated in the Gediz, Büyük Menderes and Çukurova deltas, respectively. Breeding attempts were recorded in at least seven wetlands in Turkey in the past, yet after 1999 most of the colonies were abandoned due to basin scale intensive water management practices in Central Anatolia. Currently, only Tuz Lake and Gediz Delta are used as regular breeding sites, while breeding has been recorded sporadically in Acıgöl and Akşehir Lakes. The breeding colony of Tuz Lake is of prime importance at the Mediterranean scale, with the number of young chicks in 2011, 2012 and 2013 accounting for the highest number of fledglings in the Mediterranean Region and West Africa (18,418, 20,274 and 20,292 respectively). Finally, building upon the previous findings about Turkey and the western Mediterranean metapopulation links, recent resightings of Turkish flamingos (despite the limited numbers) confirm post-fledging and natal dispersal reaching the western Mediterranean Basin and West Africa. Flamingos from Turkey were also found to disperse to Israel and to a region outside the known flyways of the western Mediterranean and West African flamingos (i.e. to Israel and UAE). Thus, Turkey, due to its geographic position, appears to be a crossroad between the western and eastern Mediterranean Region and southwest Asia.
The Dalmatian Pelican, Pelecanus crispus (Bruch, 1832), used to be a widespread breeding species in Turkey in the past. Until the 1990s, approximately 473-763 pairs were breeding at 20-25 sites. Of ...these, 53-59% have been lost due to drainage of wetlands, 17-19% due to direct persecution, 16-22% due to both drainage and persecution, and 6-8% due to water level increase. Currently there are only five active breeding colonies: Gediz Delta, Manyas Lake, Büyük Menderes Delta, Aktaş Lake and Işıklı Lake. The colony at Işıklı Lake was discovered in 2010 and comprises 6 pairs. Since 2000, the total breeding population of Dalmatian Pelicans increased moderately from 220-250 to 277-341 pairs. Likewise, the wintering population has also increased from 352 up to 2,344 individuals, which seems to be linked with the increase in the breeding population in the region. Nevertheless, the population size still renders the species susceptible to the risks affecting small populations.