Ornis Fennica 2023:4

Ornis Fennica 4/2023 contains the following articles: Adam Zbyryt, Cezary Mitrus, Grzegorz Neubauer, Productivity of the Great Egret (Ardea alba) and Grey Heron (A. cinerea) in mixed heronries in Poland and behavioral response of fledglings to a drone; Adam Søderdahl, Anders P. Tøttrup, Consistent delay in recent timing of passerine autumn migration; Elina Koivisto, Giulia Masoero, Chiara Morosinotto, Eric Le Tortorec, Erkki Korpimäki, Conspecific density drives sex-specific spatial wintertime distribution and hoarding behaviour of an avian predator.