Formation of linear dominance relationship in captive jungle crows (Corvus macrorhynchos): Implications for individual recognition

Eiichi Izawa, Shigeru Watanabe

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

Jungle crows (Corvus macrorhynchos) flexibly change their social forms depending on their age, time of the day, and the season. In the daytime, paired adults behave territorially and unpaired subadults form small flocks of ten birds, whereas at night hundreds of birds roost together. In the breeding season, pairings remain in their nest all day. This fission-fusion raises questions about the underlying social structure and the cognitive capability of jungle crows. In this study, dyadic encounters were used to investigate dominance relationships (linear or non-linear) and the underlying mechanisms in captive jungle crows. Fourteen crows were tested in 455 encounters (i.e., 5 encounters per dyad), and a stable linear dominance relationship emerged. Sex and aggressiveness were determinants as individual characteristics for dominance formation. Males dominated females, and more aggressive individuals dominated less aggressive ones. Aggressive interactions in dyads occurred primarily during the first encounter and drastically declined during subsequent encounters without any signs of a confidence effect. These results suggest that, in captive jungle crow, a linear form of dominance is intrinsically determined by sex and aggressiveness and maintained extrinsically by memories of past outcomes associated with specific individuals, implying individual recognition.

Original languageEnglish
Pages (from-to)44-52
Number of pages9
JournalBehavioural Processes
Volume78
Issue number1
DOIs
Publication statusPublished - 2008 May

Fingerprint

Crows
Corvus
crows
aggression
dominance (genetics)
bird
social structure
social change
breeding season
nest
Birds
gender
birds
flocks
Breeding
nests
Recognition (Psychology)
effect

Keywords

  • Corvid
  • Crow
  • Dominance
  • Social cognition
  • Social relationship

ASJC Scopus subject areas

  • Animal Science and Zoology
  • Ecology, Evolution, Behavior and Systematics
  • Behavioral Neuroscience

Cite this

Formation of linear dominance relationship in captive jungle crows (Corvus macrorhynchos) : Implications for individual recognition. / Izawa, Eiichi; Watanabe, Shigeru.

In: Behavioural Processes, Vol. 78, No. 1, 05.2008, p. 44-52.

Research output: Contribution to journalArticle

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