Elucidating the patterns in mid-winter waterbird surveys by using climate, lake water level fluctuations and macrophyte records

Özgencil, İbrahim Kaan
Impacts of winter climate in Eastern Europe, North Atlantic Oscillation (NAO), water level changes and submerged macrophytes on wintering waterbird community size and structure in three Turkish shallow lakes from three different geographical regions were investigated by using the Mid-Winter Waterbird Survey results from 1967-2016. The study demonstrated that average winter air temperatures in Eastern Europe and combined wintering waterbird community density of the study lakes were negatively correlated. North Atlantic Oscillation was found to have a weak impact on wintering waterbird communities of the study lakes with negative values of NAO Index showing a slight tendency to translate to more waterbird species coming to the study lakes. Although the results were variable across the study lakes, water level was discovered to have a substantial impact on various waterbird community parameters including density and species richness. The study showed that increases in submerged macrophyte abundance and diversity were mostly coupled with an increase in numbers of wintering waterbird communities, probably due to an increased availability and diversity of their food sources. Results of this study suggest that Turkey becomes a crucial wintering ground for migratory waterbirds when Eastern Europe is having a harsh winter and NAO Index reaches negative highs, and to preserve Turkish shallow lakes as high-quality wintering grounds for migratory waterbirds, lakes should be managed at proper water levels and at macrophyte-dominated states.


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Citation Formats
İ. K. Özgencil, “Elucidating the patterns in mid-winter waterbird surveys by using climate, lake water level fluctuations and macrophyte records,” M.S. - Master of Science, Middle East Technical University, 2017.