Map of the 46 study sites located in the Pannonian lowland ecoregion in Croatia. *Legend: Study sites: 1 Bednja, Stažnjevec village 2 Ždalica, Ždala village 3 Krapina, Bedekovčina village 4 Krapina, Zaprešić town 5 Krapina, Kupljenovo village 6 Krapinica, Zabok town 7 Krapinica, Krapina town 8 Rajna, between Vrbovec town and Lonjica village 9 Zlenin, Vrbovec village 10 Vukšinac, Stubice village 11 Deanovac lateral canal, near Ivanić Grad town 12 Reka, Lovrečan village 13 Brodec, Peklenica village 14 Lateral canal Mihovljan, Čakovec town 15 Poloj, between Legrad and Đelekovec villages 16 Zdelja, Molve village 17 Lonja, near Ivanić Grad town 18 Jalšovnica, Ferketinec village 19 Bošćak, Domašinec village 20 Bistrec, Rakovnica I 21 Bistrec, Rakovnica II 22 Zelina, Božjakovina village 23 Connecting canal Zelina-Lonja-Glogovnica-Česma, Poljanski lug village 24 Glogovnica, before mouth to Česma 25 Česma, Obedišće village 26 Česma, Pavlovac village 27 Česma, Sišćani village 28 Česma, Narta village 29 Sutla, Luke Poljanske village 30 Rogostrug, Podravske Sesvete village 31 Kosteljina, Jalšje village 32 Horvatska, Veliko Trgovišće village 33 Bistra Koprivnička, Molve village 34 Toplica, Sokolovac village 35 Toplica, downstream from Daruvar town 36 Toplica, upstream from Daruvar town 37 Luka, Vrbovec town 38 Sewage collector, Prelog town 39 Gornji potok, between Selnica and Praporčan villages 40 Kotoribski kanal, Kotoriba village 41 Črnec, Gornji Dubovec vilage 42 Gostiraj, Ježdovec village 43 Tomašica, Tomašica village 44 Jalšovec, between Bukovje and Štrigova villages 45 Murščak, between Domašinec and Stara Straža villages 46 Glogovnica, Koritna village.