01288nas a2200133   4500008004100000245007000041210006700111520083800178100002101016700002301037700002301060700002301083856004801106       1981                        eng d00aAn experimental investigation of the bioacoustics of cowbird song0 aexperimental investigation of the bioacoustics of cowbird song3 a<p>Female cowbirds (Molothrus ater ater), maintained in isolation from males during the breeding season, respond to the playback of male song with copulatory postures. They respond to some songs more than to others. Cowbird song potency can thus be operationally defined by the proportion of copulatory postures a song elicits across multiple playbacks. The purpose of the present study was to explore whether song potency changes with distance in the field. No field recordings elicited high levels of responding by the females. When songs of known high potency are systematically degraded, the results indicate that female cowbirds are sensitive to small changes in signal to noise ratio and to atmospheric attenuation. The data suggest that cowbird song potency degrades very rapidly with transmission distance in the field.</p>
1 aKing, Andrew, P.1 aWest, Meredith, J.1 aEastzer, David, H.1 aStaddon, J., E. R.  uhttp://link.springer.com/10.1007/BF00302940