Behavioral Ecology and Sociobiology

, Volume 66, Issue 11, pp 1503–1509 | Cite as

Soft song is a reliable signal of aggressive intent in song sparrows

  • Christopher N. Templeton
  • Çağlar Akçay
  • S. Elizabeth Campbell
  • Michael D. Beecher
Original Paper


Animals frequently use signals to modulate aggressive interactions. Establishing that a signal is aggressive or threatening requires demonstrating that it is more commonly used in agonistic contexts, that it predicts subsequent aggressive behaviors by the sender, and that receivers respond differently to this signal. Like many birds, song sparrows (Melospiza melodia) produce a low-amplitude “soft song” vocalization that has been hypothesized to be an aggressive signal. Soft song meets the first two criteria, but previous research has failed to demonstrate that soft song provokes aggression or that receivers even perceive soft song differently from normal loud song. We used a playback experiment with taxidermic mount presentation to test whether territorial male song sparrows respond differently to loud and soft song playbacks. Subjects reacted more strongly to the soft song playback by approaching the mount more closely, increasing wing wave displays, and increasing the proportion of their own songs that were soft songs, with further trends toward increasing the number of flights and attacks. These results confirm that soft song is a conventional signal of aggression in song sparrows and that increased receiver retaliation maintains its reliability.


Aggression Bird song Honest signaling Song sparrow Territoriality 


  1. Akçay Ç, Tom M, Holmes D, Campbell SE, Beecher MD (2011) Sing softly and carry a big stick: Soft song as an aggressive signal in song sparrows. Anim Behav 82:377–382CrossRefGoogle Scholar
  2. Anderson RC, Nowicki S, Searcy WA (2007) Soft song in song sparrows: Response of males and females to an enigmatic signal. Behav Ecol Sociobiol 61:1267–1274CrossRefGoogle Scholar
  3. Anderson RC, Searcy WA, Hughes M, Nowicki S (2012) The receiver-dependent cost of soft song: A signal of aggressive intent in songbirds. Anim Behav 83:1443–1448CrossRefGoogle Scholar
  4. Anderson RC, Searcy WA, Peters S, Nowicki S (2008) Soft song in song sparrows: Acoustic structure and implications for signal function. Ethology 114:662–676CrossRefGoogle Scholar
  5. Arcese P, Sogge MK, Marr AB, Patten MA (2002) Song sparrow (Melospiza melodia). The Birds of North America Online database: Accessed 14 Oct 2011
  6. Ballentine B, Searcy WA, Nowicki S (2008) Reliable aggressive signalling in swamp sparrows. Anim Behav 75:693–703CrossRefGoogle Scholar
  7. Beecher MD (2008) Function and mechanisms of song learning in song sparrows. Adv Stud Behav 38:167–225CrossRefGoogle Scholar
  8. Brumm H (2009) Song amplitude and body size in birds. Behav Ecol Sociobiol 63:1157–1165CrossRefGoogle Scholar
  9. Brumm H, Ritschard M (2011) Song amplitude affects territorial aggression of male receivers in chaffinches. Behav Ecol 22:310–316CrossRefGoogle Scholar
  10. Brumm H, Todt D (2004) Male–male vocal interactions and the adjustment of song amplitude in a territorial bird. Anim Behav 67:281–286CrossRefGoogle Scholar
  11. Catchpole CK, Slater PJB (2008) Bird song: biological themes and variations, 2nd edn. Cambridge University Press, CambridgeCrossRefGoogle Scholar
  12. Clutton-Brock TH, Albon SD (1979) Roaring of red deer and the evolution of honest advertisement. Behaviour 69:145–170CrossRefGoogle Scholar
  13. Dabelsteen T, McGregor PK, Lampe HM, Langmore NE, Holland J (1998) Quiet song in song birds: An overlooked phenomenon. Bioacoustics 9:89–105CrossRefGoogle Scholar
  14. Dabelsteen T, Pedersen SB (1990) Song and information about aggressive responses of blackbirds, Turdus merula: Evidence from interactive playback experiments with territory owners. Anim Behav 40:1158–1168CrossRefGoogle Scholar
  15. Davies NB, Halliday TR (1978) Deep croaks and fighting assessment in toads Bufo bufo. Nature 274:683–685CrossRefGoogle Scholar
  16. Gil D, Gahr M (2002) The honesty of bird song: Multiple constraints for multiple traits. Trends Ecol Evol 17:133–141CrossRefGoogle Scholar
  17. Grafen A (1990) Biological signals as handicaps. J Theor Biol 144:517–546PubMedCrossRefGoogle Scholar
  18. Hof D, Hazlett N (2010) Low-amplitude song predicts attack in a North American wood warbler. Anim Behav 80:821–828CrossRefGoogle Scholar
  19. Krebs J, Ashcroft R, Webber M (1978) Song repertoires and territory defence in great tit. Nature 271:539–542CrossRefGoogle Scholar
  20. Lack D (1965) The life of the robin. Witherby, LondonGoogle Scholar
  21. Lampe HM, Balsby TJS, Espmark YO, Dabelsteen T (2010) Does twitter song amplitude signal male arousal in redwings (Turdus iliacus)? Behaviour 147:353–365CrossRefGoogle Scholar
  22. Maynard Smith J (1974) Theory of games and evolution of animal conflicts. J Theor Biol 47:209–221CrossRefGoogle Scholar
  23. Maynard Smith J (1979) Game theory and the evolution of behavior. Proc Roy Soc Lond B 205:475–488CrossRefGoogle Scholar
  24. Maynard Smith J, Harper D (2003) Animal signals. Oxford University Press, OxfordGoogle Scholar
  25. McDonald MV (1989) Function of song in Scott’s seaside sparrow, Ammodramus maritimus peninsulae. Anim Behav 38:468–485CrossRefGoogle Scholar
  26. Molles LE, Vehrencamp SL (2001) Songbird cheaters pay a retaliation cost: Evidence for auditory conventional signals. Proc Roy Soc Lond B 268:2013–2019CrossRefGoogle Scholar
  27. Nakagawa S, Cuthill IC (2007) Effect size, confidence interval and statistical significance: A practical guide for biologists. Biol Rev 82:591–605PubMedCrossRefGoogle Scholar
  28. Nice MM (1943) Studies in the life history of the song sparrow. II The behavior of the song sparrow and other passerine birds Trans Linn Soc NY 6:1–329Google Scholar
  29. Nowicki S, Searcy WA, Hughes M (1998) The territory defense function of song in song sparrows: A test with the speaker occupation design. Behaviour 135:615–628CrossRefGoogle Scholar
  30. Peters S, Searcy WA, Beecher MD, Nowicki S (2000) Geographic variation in the organization of song sparrow repertoires. Auk 117:936–942Google Scholar
  31. Podos J, Peters S, Rudnicky T, Marler P, Nowicki S (1992) The organization of song repertoires in song sparrows: Themes and variations. Ethology 90:89–106CrossRefGoogle Scholar
  32. Reichard DG, Rice RJ, Vanderbilt CC, Ketterson ED (2011) Deciphering information encoded in birdsong: Male songbirds with fertile mates respond most strongly to complex, low-amplitude songs used in courtship. Am Nat 178:478–487PubMedCrossRefGoogle Scholar
  33. Rek P, Osiejuk TS (2011) Nonpasserine bird produces soft calls and pays retaliation cost. Behav Ecol 22:657–662CrossRefGoogle Scholar
  34. Ritschard M, van Oers K, Naguib M, Brumm H (2012) Song amplitude of rival males modulates the territorial behaviour of great tits during the fertile period of their mates. Ethology 118:197–202CrossRefGoogle Scholar
  35. Rohwer S, Rohwer FC (1978) Status signaling in harris sparrows: Experimental deceptions achieved. Anim Behav 26:1012–1016CrossRefGoogle Scholar
  36. Searcy WA, Anderson RC, Nowicki S (2006) Bird song as a signal of aggressive intent. Behav Ecol Sociobiol 60:234–241CrossRefGoogle Scholar
  37. Searcy WA, Beecher MD (2009) Song as an aggressive signal in songbirds. Anim Behav 78:1281–1292CrossRefGoogle Scholar
  38. Searcy WA, Nowicki S (2005) The evolution of animal communication: reliability and deception in signaling systems. Princeton University Press, PrincetonGoogle Scholar
  39. Searcy WA, Podos J, Nowicki S, Peters S (1995) Discrimination of song types and variants in song sparrows. Anim Behav 49:1219–1226CrossRefGoogle Scholar
  40. Stoddard PK, Beecher MD, Willis MS (1988) Response of territorial male song sparrows to song types and variations. Behav Ecol Sociobiol 22:125–130CrossRefGoogle Scholar
  41. Templeton CN, Campbell SE, Beecher MD (2012) Territorial song sparrows tolerate juveniles during the early song-learning phase. Behav Ecol 23:916–923CrossRefGoogle Scholar
  42. Tibbetts EA, Dale J (2004) A socially enforced signal of quality in a paper wasp. Nature 432:218–222PubMedCrossRefGoogle Scholar
  43. Titus RC (1998) Short-range and long-range songs: Use of two acoustically distinct song classes by dark-eyed juncos. Auk 115:386–393CrossRefGoogle Scholar
  44. Zahavi A (1975) Mate selection—a selection for a handicap. J Theor Biol 53:205–214PubMedCrossRefGoogle Scholar
  45. Zahavi A (1977) The cost of honesty (further remarks on handicap principle). J Theor Biol 67:603–605PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Christopher N. Templeton
    • 1
    • 3
  • Çağlar Akçay
    • 2
    • 4
  • S. Elizabeth Campbell
    • 1
    • 2
  • Michael D. Beecher
    • 1
    • 2
  1. 1.Department of BiologyUniversity of WashingtonSeattleUSA
  2. 2.Department of PsychologyUniversity of WashingtonSeattleUSA
  3. 3.School of BiologyUniversity of St AndrewsSt AndrewsUK
  4. 4.Cornell Lab of OrnithologyCornell UniversityIthacaUSA

Personalised recommendations