Adam Zbyryt, Sebastian Menderski
Ornis Polonica 2017, 58: 197–202
https://doi.org/10.12657/ornis.2017.3.4
Abstract: We compared two techniques of counting Grey Heron Ardea cinerea nests in a breeding colony: (1) with marking and (2) without marking of the nesting trees. We conducted the study in 13 randomly selected colonies of Grey Herons located in N Poland in 2017. Counts without marking of nest trees resulted in 17–36% underestimation of the nest number. We recommend the usage of a drone for inspections of Great Egret A. alba and Grey Heron nests, situated in reedbeds and mixed colonies of these species located on shrubs and trees. The method using a drone is faster than traditional methods, and allows for collecting of more precise information. At the same time it creates much less disturbance to the breeding birds.
