Summary: | The aim of this study was to examine what impact restored and constructed pounds and wetlands have on waterfowls in the area of Linköping. The birdlife in five constructed wetlands werechosen to investigate if specific factors like age, size and vegetation affected the avian diversity in wetlands. Also, extra focus has been given to the threatened Horned Grebe (Podiceps Auritus), breeding in the studied area. The results showed that the number of species as well as individuals of waterfowl and Horned Grebe changed over time in what might be a result of succession in the wetlands. Comparing the number of birds to the size of the wetlands showed a clear correlation. Larger areas inhabited greater numbers of species and individuals. However, the Horned Grebe showed a reverse result, as they seem to prefer smaller wetlands. Finally, a correlation between the numbers of observed Black-headed gulls and Horned Grebes could be found. When there was a greater number of Horned Grebes observed there was also a greater numbers of gulls present. Possibly the Horned Grebe takes advantage of the Black-headed gull-colony for protection against predators.
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