© Mathias Schäf
Breeding bird index
for 174 regular breeders 1990–2018.
Knaus, P., T. Sattler, H. Schmid & N. Strebel (2019): The State of Birds in Switzerland 2019 online. http://www.vogelwarte.ch/state. Swiss Ornithological Institute, Sempach.
© Mathias Schäf
for 174 regular breeders 1990–2018.
Knaus, P., T. Sattler, H. Schmid & N. Strebel (2019): The State of Birds in Switzerland 2019 online. http://www.vogelwarte.ch/state. Swiss Ornithological Institute, Sempach.