Vol. 77 2025

ARTICLES

Long-Term Changes in the Breeding Success of the Dalmatian Pelican Colony in the Srebarna Nature Reserve (NE Bulgaria) and Conservation Measures Over the Years

Nevena Ivanova1*, Pavel Simeonov2, Momchil Petrov3, Martin P. Marinov1 & Boyan T. Michev1

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*1Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, Sofia 1113, Bulgaria; E-mail: nevena759344@gmail.com, martin.marinov@iber.bas.bg, michevboyan@gmail.com,
2Le Balkan – Bulgaria Foundation, Branta Conservation Centre, Durankulak 9670 Bulgaria; lebalkan@lebalkan.org
3Regional Inspectorate of Environment and Water – Ruse, Ruse, Bulgaria; E-mail: pr.srebarna@riosv-ruse.org

https://doi.org/10.71424/azb77.4.002835

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Abstract

Long-term population studies are of great importance in ecology and conservation. We present a comprehensive analysis of long-term data (1955–2024) on numbers of nests and breeding success of the colony of the Dalmatian pelican (Pelecanus crispus) in the Srebarna Nature Reserve, Bulgaria. The variation in breeding success was estimated by the number of chicks successfully raised per occupied nest, indicating a significant overall increase. The number of nests ranged from 7 to 150 over the years and had a noticeable downward trend in the last five years. We evaluated various conservation measures implemented in the reserve, such as the construction of raised wooden platforms and the establishment of protective fences, highlighting their effectiveness in maintaining the breeding colony. Our findings indicated that although breeding success had improved over the decades, recent declines in nest numbers were linked to external factors, including human disturbance, predation by invasive species and the availability of alternative nesting sites in other protected areas. We call for continuation of the conservation efforts to enhance the long-term viability of the Dalmatian pelican population in the reserve.

Key words

breeding ecology, Danube River, long-term data, Pelecanus crispus, water birds

How to Cite
Ivanova N., Simeonov P., Petrov M., Marinov M. P. & Michev B. T. 2025. Long-Term Changes in the Breeding Success of the Dalmatian Pelican Colony in the Srebarna Nature Reserve (Ne Bulgaria) and Conservation Measures Over the Years. Acta zoologica bulgarica 77 (4): 479-494.

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