Song sparrows (Melospiza melodia; Emberizidae) reliably broadcast information about perceived threats using alarm calls

WCU Author/Contributor (non-WCU co-authors, if there are any, appear on document)
Jennifer Nicole Carman (Creator)
Institution
Western Carolina University (WCU )
Web Site: http://library.wcu.edu/
Advisor
Greg Adkison

Abstract: Expanding our understanding of signal complexity in animals could start with thevery smallest songbirds. Black-capped Chickadees (Poecile atricapillus) can encodevery specific details about a threat in their acoustically simple alarm calls. Can othersmall songbird species, such as the Song sparrow (Melospiza melodia), encode thatsame level of detail in their even simpler alarms? Furthermore, is it possible for them tointerpret those details, and are those details reliable? I measured the response of Songsparrows to the suggestion of a threat (two recordings of Song sparrow alarms, one inwhich the call elements were played much faster than a normal call and one in whichthey were played much slower) then, separately, to the threat itself (a taxadermic mountof an Eastern screech owl, Megascops asio), and then to a non-threating control (aNorthern bobwhite, Colinus virginianus). The Song sparrows consistently approachedthe speaker more closely when they heard a faster alarm call and also produced afaster alarm call in response to the more threatening screech owl mount. This suggeststhat there is specific data encoded in the alarms and that they will produce a differentalarm according to the perceived threat level of what they are encountering.

Additional Information

Publication
Thesis
Language: English
Date: 2015
Keywords
alarm call, bird call, duty cycle, Melospiza melodia, ornithology, Song sparrow
Subjects
Song sparrow -- Vocalization
Song sparrow -- Behavior
Birdsongs

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