{"data":[{"source":"bio.acousti.ca","id":"58415","type":"article","title":"Use of simple graded signals in the long-distance vocal communication of a forest thrush ( Catharus fuscescens )","author":"Heckscher, Christopher M.","editor":null,"year":"2021","month":null,"journal":null,"booktitle":null,"series":null,"howpublished":null,"volume":null,"number":null,"pages":null,"chapter":null,"edition":null,"publisher":null,"organization":null,"institution":null,"school":null,"address":null,"type_of_work":null,"note":null,"isbn":null,"issn":null,"doi":"10.1080\/09524622.2021.1888316","url":"https:\/\/www.tandfonline.com\/doi\/full\/10.1080\/09524622.2021.1888316","attachments":"https:\/\/bio.acousti.ca\/sites\/default\/files\/Use%20of%20simple%20graded%20signals%20in%20the%20long%20distance%20vocal%20communication%20of%20a%20forest%20thrush%20Catharus%20fuscescens.pdf","keywords":"Assessment\/Management; Catharus; motivation-structural rules; Songbird; Veery","abstract":"I investigated the use of simple graded structures (i.e. \u2018calls\u2019) in long-distance vocal communication among territorial forest-dwelling Catharus fuscescens \u2013 an oscine passerine that also possesses a complex song. Two experiments were conducted: (1) Nests were threatened in three different contexts to test the effect of increasing motivation on three response variables (call form, rate, amplitude), and (2) a playback study was undertaken to quantify the accomplishments of graded call structures on territory-holders. Results from the two experiments showed that long-distance communication in the focal species is dependent on two concurrent aspects of communication: (1) Acoustic cues to signaller motivation via call rate, (2) spectral cues that reveal directivity \u2013 either precisely or imprecisely \u2013 that complement the perception of signaller location via distance assessment (ranging). Simultaneously, amplitude and bandwidth are adjusted to beam signals across various distance intervals. Therefore, to affect conspecific behaviour, a signaller can alter vocal cues to manipulate an assessor\u2019s perception of signaller location while revealing motivation. This study reveals the foundational components of short and long-distance communication with the use of simple graded calls by a forest-dwelling oscine passerine. It is similar to long-distance communication networks documented in some parrots, marine mammals, and primates.","type_name":"Journal Article","journal_abbreviation":null,"pmid":null,"info_url":"https:\/\/bio.acousti.ca\/node\/58415"}]}