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Öğe Current status of the Dalmatian pelican and the great white pelican populations of the Black Sea/Mediterranean flyway(Inter-Research, 2015) Catsadorakis, Giorgos; Onmus, Ortac; Bugariu, Sebastian; Gul, Orhan; Hatzilacou, Dionyssia; Hatzofe, Ohad; Malakou, Myrsini; Michev, Tanyo; Naziridis, Theodoros; Nikolaou, Haris; Rudenko, Antonina; Saveljic, Darko; Shumka, Spase; Siki, Mehmet; Crivelli, Alain J.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.Öğe Significant Impacts of the Water Level and Human Intervention on the Natural Habitats and Breeding Waterbirds in Marmara Lake(Foundation Environmental Protection & Research-Fepr, 2013) Gul, Orhan; Onmus, Ortac; Siki, MehmetHabitat cover and change were analysed in the Marmara Lake to investigate the effects of water level and human intervention on the natural habitats and breeding waterbirds. Breeding Birds Surveys were applied to investigate breeding waterbirds and their breeding activities in 2008 and 2011. GIS, remote sensing techniques and various satellite images were used to determine distributions, surface areas, zonal centroids, and displacements of the habitats in 2000, 2008 and 2011. The total number of bird species with and without breeding evidence in 2008 and 2011 were compared with the Chi-Square test. Habitats in each UTM grid in 2008 and 2011 were compared with McNemar's test. The impact of water level on habitats, number of breeding birds, and their breeding parameters were investigated using Spearman's correlation analyses. The major habitats were open waters, reed beds, scrubs and woodlands, wet grasslands, and mudflats. Significant increases were observed in open waters, reed beds, and wet grasslands, but no significant change was observed for scrubs and woodlands. Out of 70 UTM grids, 69 and 48 grids corresponding to 95 and 75 observation points were surveyed in 2008 and 2011, and 34 different waterbirds were identified. The total number of breeding waterbirds significantly increased in 2011. Open waters were positively correlated with reed beds and negatively correlated with mudflats. Among 34 waterbird species, changes in the breeding parameters of 22 species were significantly correlated with the changes occurring in the major habitats. Our study demonstrates that changes in water level significantly affected the existence of key habitats and theirs distributions, resulting in significant changes in the number of breeding waterbirds and their breeding activities.Öğe Significant Impacts of the Water Level and Human Intervention on the Natural Habitats and Breeding Waterbirds in Marmara Lake(Foundation Environmental Protection & Research-Fepr, 2013) Gul, Orhan; Onmus, Ortac; Siki, MehmetHabitat cover and change were analysed in the Marmara Lake to investigate the effects of water level and human intervention on the natural habitats and breeding waterbirds. Breeding Birds Surveys were applied to investigate breeding waterbirds and their breeding activities in 2008 and 2011. GIS, remote sensing techniques and various satellite images were used to determine distributions, surface areas, zonal centroids, and displacements of the habitats in 2000, 2008 and 2011. The total number of bird species with and without breeding evidence in 2008 and 2011 were compared with the Chi-Square test. Habitats in each UTM grid in 2008 and 2011 were compared with McNemar's test. The impact of water level on habitats, number of breeding birds, and their breeding parameters were investigated using Spearman's correlation analyses. The major habitats were open waters, reed beds, scrubs and woodlands, wet grasslands, and mudflats. Significant increases were observed in open waters, reed beds, and wet grasslands, but no significant change was observed for scrubs and woodlands. Out of 70 UTM grids, 69 and 48 grids corresponding to 95 and 75 observation points were surveyed in 2008 and 2011, and 34 different waterbirds were identified. The total number of breeding waterbirds significantly increased in 2011. Open waters were positively correlated with reed beds and negatively correlated with mudflats. Among 34 waterbird species, changes in the breeding parameters of 22 species were significantly correlated with the changes occurring in the major habitats. Our study demonstrates that changes in water level significantly affected the existence of key habitats and theirs distributions, resulting in significant changes in the number of breeding waterbirds and their breeding activities.Öğe Significant ımpacts of the water level and human iAntervention on the natural habitats and breeding waterbirds in marmara lake(2013) Gul, Orhan; Onmuş, Ortaç; Sıkı, MehmetMarmara Gölü’nde, su seviyesi ve insan müdahalesine bağlı olarak doğal habitatlar ve üreyen sukuşlarında meydana gelen değişimler, habitat dağılımı ve değişimi analiz edilerek incelenmiştir. 2008 ve 2011 yıllarında, üreyen su kuşu türlerini ve üreme aktivitelerini tespit etmek amacıyla üreyen kuşlar atlas çalışması gerçekleştirilmiştir. Habitatların 2000, 2008 ve 2011 yıllarındaki dağılımlarını, yüzey alanlarını, ağırlık merkezlerini ve değişimlerini belirlemek için Coğrafi Bilgi Sistemleri, uzaktan algılama teknikleri ve çeşitli uydu görüntüleri kullanılmıştır. 2008 ve 2011 yıllarında üreyen sukuşu sayısı ve üreme durumları ki-kare analizi ile incelenmiştir. Her bir habitat tipinin 2008’de var olduğu UTM karelerinin 2011’deki durumu McNemar analizi ile karşılaştırılmıştır. Su seviyesinin habitatlar, üreyen sukuşları ve üreme aktiviteleri üzerine olan etkileri Spearman korelasyon analizi ile incelenmiştir. Açık su yüzeyi, sazlıklar, çalı ve ağaç toplulukları, sulak çayırlar ve çamur düzlükleri Marmara Gölü’ndeki temel habitatlardır. 2011 yılında, açık su yüzeyi, sazlıklar ve sulak çayırlar için anlamlı artışlar gözlenirken, çalı ve ağaç toplulukları için bir fark bulunamamıştır. Üreyen kuşlar atlas çalışmalarında toplam 70 UTM karesinden, 2008 yılında 69 UTM karesi ve 95 noktada, 2011 yılında ise 48 UTM karesi ve 75 noktada gözlem yapılmış; iki çalışma genelinde 34 su kuşu türünün ürediğine dair bulgular elde edilmiştir. 2011 yılında alanda üreyen sukuşu sayısında istatistiksel olarak anlamlı artış saptanmıştır. Açık su yüzeyindeki artışa bağlı olarak sazlıklar pozitif, çamur düzlükleri ise negatif korelasyon göstermiştir. Üreme kodu verilen 34 sukuşu türünden 22’sinin üreme parametreleri, temel habitatlarda gözlenen değişimlerle anlamlı korelasyon göstermiştir. Araştırmamız, bir göldeki su seviyesinde meydana gelen değişimin temel habitatların varlığını ve dağılımını doğrudan etkilediğini ve buna bağlı olarak alanda üreyen sukuşlarının sayısını ve üreme aktivitelerini de önemli ölçüde etkilediğini göstermiştir.
