S. L. Finkbeiner Douglas H. Johnson T. Allen 2004 We compared detection rates of passive and playback breeding bird survey techniques on elusive marsh birds - Pied-billed Grebe (Podilymbus podiceps), American Bittern (Botaurus lentiginosus), Least Bittern (Ixobrychus exilis), Virginia Rail (Rallus limicola), and Sora (Porzana carolina) - during a two-year study at Lacreek National Wildlife Refuge, in southwestern South Dakota. We conducted 151 passive point counts followed by playback-response surveys at the same points in marsh-bird habitat on the refuge. Playback surveys detected secretive water birds more frequently than our passive surveys, increasing rates for each species by factors of 2.4 to 7.0. The distance a bird was detected from a point varied with the species and the survey technique. application/pdf 10.1675/1524-4695(2004)027[0277:CODROB]2.0.CO;2 en The Waterbird Society Comparison of detection rates of breeding marsh birds in passive and playback surveys at Lacreek National Wildlife Refuge, South Dakota article