26.06.2023: Human-induced environmental pollution has a significant impact and even influences the nestbuilding of birds. This is shown by a recent European study led by the Konrad Lorenz Institute of Ethology at Vetmeduni using storks. However, the use of human waste differs significantly between individual stork populations.

Two major consequences of the ever-increasing human expansion are the conversion of natural habitats into agricultural land and the expansion of built-up areas. Related to this, human waste is also found just about everywhere. This has serious implications: Plastic pollution, in particular, is impacting wildlife worldwide. Discarded plastic is ubiquitous and increasingly a material for birds to incorporate into their nest structure - as now shown by a European research team from Spain, Poland and Austria using the white stork (Ciconia ciconia) as an example. In their study, the scientists describe the type, frequency and amount of anthropogenic nesting materials in two populations of the white stork in two geographically distant breeding areas, namely in Poland and in Spain.

Poland is not Spain: Significant differences in the use of plastic

In the total of 303 nests of the two populations, the researchers found significant differences in the use of anthropogenic nesting materials. To explain the reason of this, the scientist:in used remote sensing data from the Human Footprint Index (HFI) and the proportion of Impervious Surface Areas (ISA) - covered by buildings, roads and similar man-made structures. "We found that both ISA and HFI were positively related to the amount of anthropogenic nesting materials in the Spanish population. In contrast, there were no statistically significant correlations in the Polish population," said study final author Marcin Tobółka of the Vetmeduni's Konrad Lorenz Institute of Ethology. In addition, the researchers:in were able to demonstrate that the use of anthropogenic nesting material in Spain was twice as high as in the Polish white stork population.