Study area and species
The study was carried out on colonial and gregarious species of
waterbirds in northern Poland (Europe). Most of the observations were
made in the lower course and estuary of a large lowland river – the
Lower Oder Valley (site-centre location in decimal degrees: Longitude -
14.413200, Latitude - 53.085000). The observations were made in areas
known for their importance for waterbirds, during the breeding season,
migration, and the wintering period. (Ławicki et al. 2010, Marchowski et
al. 2018).
The study covered a total of 33 species of waterbirds, including 15
breeding and 28 non-breeding species. The responses of 10 species to the
drone in both the breeding and non-breeding periods were compared.
Table 1. List of species surveyed using a drone.