Issues and controversies of cowbird management

ORTEGA, C.P; A. CRUZ; M.E. MERMOZ

Ornithological Monographs

American Ornithologist's Union

Año: 2005 vol. 57 p. 8 - 15

—Brood parasitic Brown-headed Cowbirds (Molothrus ater) have been implicated in the Federally-endangered status of fi ve hosts as well as in declines of numerous other Nearctic-Neotropical passerines that breed in North America. Cowbird control is an integral management strategy in the recovery plans of all fi ve hosts. Although there are a few exceptions, a line appears to be drawn between managers, whose main objectives are to increase host population numbers, mainly through cowbird control, and academic researchers, who want empirical evidence that cowbirds cause declines and that cowbird control actually works. The objectives here are to (1) provide a brief summary of the status of cowbird hosts, (2) provide a background of when and why cowbird management became controversial, (3) discuss the federal laws protecting cowbirds and inconsistencies in interpretation of laws, and (4) discuss some concerns about wide-scale cowbird control, and (5) discuss some management issues regarding Bronzed Cowbirds (M. aeneus) and Shiny Cowbirds (M. bonariensis) are also briefl y discussed.Molothrus ater) have been implicated in the Federally-endangered status of fi ve hosts as well as in declines of numerous other Nearctic-Neotropical passerines that breed in North America. Cowbird control is an integral management strategy in the recovery plans of all fi ve hosts. Although there are a few exceptions, a line appears to be drawn between managers, whose main objectives are to increase host population numbers, mainly through cowbird control, and academic researchers, who want empirical evidence that cowbirds cause declines and that cowbird control actually works. The objectives here are to (1) provide a brief summary of the status of cowbird hosts, (2) provide a background of when and why cowbird management became controversial, (3) discuss the federal laws protecting cowbirds and inconsistencies in interpretation of laws, and (4) discuss some concerns about wide-scale cowbird control, and (5) discuss some management issues regarding Bronzed Cowbirds (M. aeneus) and Shiny Cowbirds (M. bonariensis) are also briefl y discussed.M. aeneus) and Shiny Cowbirds (M. bonariensis) are also briefl y discussed.