Shackleton, S. A. & Ratcliffe, L. 1994: Matched counter-singing signals escalation of aggression in black-capped chickadees (Parus atricapillus). Ethology 97, 310–316.
Matched Counter-singing Signals Escalation of Aggression in Black-capped Chickadees (Parus atricapillus)
Article first published online: 26 APR 2010
1994 Blackwell Verlag GmbH
Volume 97, Issue 4, pages 310–316, January-December 1994
How to Cite
Shackleton, S. A. and Ratcliffe, L. (1994), Matched Counter-singing Signals Escalation of Aggression in Black-capped Chickadees (Parus atricapillus). Ethology, 97: 310–316. doi: 10.1111/j.1439-0310.1994.tb01049.x
- Issue published online: 26 APR 2010
- Article first published online: 26 APR 2010
- Received: November 1, 1993; Accepted: April 8, 1994 (J. Brockmann)
Black-capped chickadees (Parus atricapillus) have the ability to shift their songs up and down over a wide range of absolute frequencies. Males can shift their songs over 465 ± 52.9 (SE) Hz. During the dawn chorus, males shift their songs by 80 Hz or more every 41 ± 8.8 (SE) songs, but it appears that males can sing at any frequency within their range. Frequency shifting may allow males to match counter-sing with rival males; that is, to switch song output to match that of a rival. During simultaneously recorded dawn choruses, however, there was no correlation over time in the frequency of neighbouring males' songs, nor was there a correlation over time in the size of shifts between their songs. Moreover, males did not match the frequencies of songs presented on a played-back tape at the edge of their territories during the dawn chorus. Matching was observed during some bouts of counter-singing between males. In these cases, matched counter-singing was highly associated with escalation of the conflict. We suggest that frequency matching in this species may be a graded signal that allows the singer to direct aggression towards a particular rival.