Human activities can hinder the breeding of a top avian predator: preliminary results
Dobromir Dobrev, Vladimir Dobrev, Dimitar Demerdzhiev
An overview of monitoring for raptors in Bulgaria
Svetoslav Spasov, Volen Arkumarev, Dobromir Dobrev, Vladimir Dobrev
The Goosander Mergus merganser range expansion on the Balkan Peninsula and a new breeding population in Bulgaria
Dobromir Dobrev, Borislav Borisov, Vladimir Dobrev, Volen Arkumarev, Ivaylo Angelov, Stoycho Stoychev