01971nas a2200121   4500008004100000245012700041210006900168260001600237490000600253520151000259100002601769856005401795       2019                        eng d00aNoise-induced vocal plasticity in urban white-crowned sparrows does not involve adjustment of trill performance components0 aNoiseinduced vocal plasticity in urban whitecrowned sparrows doe  cJan-12-20190 v93 a<p>Background noise can interfere with acoustic communication and subsequently influence signaling behavior. Immediate signaling flexibility (ISF) is a context-dependent form of behavioral plasticity that allows animals to temporarily change their acoustic behavior in response to noise fluctuations and potentially improve the chances of successful communication in noisy environments. The adaptive value of ISF is ultimately contingent on the response of the intended receiver, and there are differential effects on receiver response depending on which signal component is modified. However, there is scant research on whether ISF involves modification of a signal component specifically linked to mate attraction or territory defense. Our study addresses this knowledge gap and provides important insight into whether males employ short-term signal modification in a manner that could affect mate pairing success in birds. Specifically, we explore the maladaptive potential of ISF in the San Francisco, California population of Zonotrichia leucophrys nuttalli by testing for changes in trill bandwidth and rate&mdash;the specific trill structure components known to influence the receiver&rsquo;s perception of vocal performance in this species&mdash;before and during noise broadcast experiments. Although Zonotrichia leucophrys nuttalli are capable of ISF, we found no evidence that noise induces temporary adjustment of the trill structure traits used by receivers to assess vocal performance.</p>
1 aGentry, Katherine, E.  uhttp://www.nature.com/articles/s41598-018-36276-502443nas a2200133   4500008004100000245010000041210006900141260002000210300001100230490000600241520199200247100002602239856004402265       2017                        eng d00aSpatiotemporal patterns of avian vocal activity in relation to urban and rural background noise0 aSpatiotemporal patterns of avian vocal activity in relation to u  cApr-26-20172062  aZ9TQHU0 v13 a<p>Background noise can interfere with and influence acoustic communication behavior. Signal interference is dependent on the amplitude and spectral characteristic of background noise, which varies over space and time. The likelihood of signal interference is greater when background noise is concentrated within the same frequency bands of an animal&rsquo;s vocalization, but even a partial masking effect can elicit signaling behavior modification. Relative to a rural landscape, background noise in an urban landscape is disproportionately comprised by anthropogenic sound, which fluctuates in amplitude throughout the day and occurs primarily in low frequencies (0&ndash;2 kHz). In this study, we examined if urban-rural differences in vocal activity patterns exist in a species Zonotrichia leucophrys nuttalli that communicates above the frequency range of anthropogenic noise (2&ndash;8 kHz). We tested whether vocal activity patterns changed in relation to sound in the high or low frequency bands within and between urban and rural locations. Automated acoustic recording devices (ARDs) continuously recorded throughout the morning song chorus, 0500 to 1,100 h, during the 2014 breeding season in San Francisco (urban) and Marin (rural) Counties, CA. Supervised learning cluster analysis was used to quantify vocal activity by totaling the number of songs. In general, vocal activity was greater in urban locations compared to rural locations. However, within rural and urban study sites, we found vocal activity decreased where low frequency noise levels were higher. There was not a relationship between vocal activity and high frequency, biotic sound. In both urban and rural locations, low frequency noise levels increased through the morning, while vocal activity remained relatively consistent. Our results demonstrate how patterns of vocal activity can change with low frequency, abiotic noise, even when there is no direct spectral overlap with the acoustic signal.</p>
1 aGentry, Katherine, E.  uhttps://bio.acousti.ca/pt-pt/node/52600