When are neighbours ‘dear enemies’ and when are they not? The responses of territorial male variegated pupfish, Cyprinodon variegatus, to neighbours, strangers and heterospecifics

  title={When are neighbours ‘dear enemies’ and when are they not? The responses of territorial male variegated pupfish, Cyprinodon variegatus, to neighbours, strangers and heterospecifics},
  author={John K. Leiser},
  journal={Animal Behaviour},
  • J. Leiser
  • Published 1 March 2003
  • Psychology
  • Animal Behaviour
Abstract Dear enemy recognition reduces the costs of territorial defence in some species, but not others, when a neighbour is more threatening to a resident's fitness than an intruder. I asked whether dear enemy effects were fixed in a particular species, or if the reduced aggression between a resident and neighbour was disrupted by the presence of potential mating opportunities. Observing variegated pupfish, Cyprinodon variegatus , in the field and in the laboratory, I examined the effects of… 

Responses to neighbours and non-neighbours in the buff-banded rail (Gallirallus philippensis): no dear-enemy relationships

No evidence for the dear-enemy phenomenon was found in an insular population of territory-holding buff-banded rails and males and females were shown to differ qualitatively in their general territorial response to intruders, suggesting that the relative threats posed by neighbours and non-neighbours do not differ between the sexes.

Dear Enemies Elicit Lower Androgen Responses to Territorial Challenges than Unfamiliar Intruders in a Cichlid Fish

It is suggested that the dear enemy effect modulates the androgen response to territorial intrusions and that repeated intrusions lead to a habituation of the androgens response.

Vocal behaviour reveals asymmetries in neighbour relationships in a semi-colonial raptor, the Eurasian Scops Owl Otus scops

Territorial animals often reduce aggression towards familiar neighbours compared to unfamiliar conspecifics. However, variation in the response to different neighbours is less known. In this work, I

Tit for Tat in the Dear Enemy Relationship Between Territorial Females of a Cichlid Fish

Focal fish attacked invading neighbours as frequently as invading strangers, but they immediately stopped attacking the dear neighbour after the neighbour returned to its own territory, whereas they kept attacking strangers even after they stopped invading.

‘Nasty neighbours’ rather than ‘dear enemies’ in a social carnivore

It is suggested that increased aggression towards neighbours is more common in social species with intense competition between neighbours, as opposed to reduced aggression against neighbours typical for most solitary species.



The role of neighbours in territorial systems: when are they 'dear enemies'?

  • E. Temeles
  • Environmental Science
    Animal Behaviour
  • 1994
Abstract Abstract. Many territorial animals respond less aggressively to neighbours than to strangers (the dear enemy phenomenon). The dear enemy phenomenon generally has been assumed to represent

Dear Enemy Recognition and the Costs of Aggression between Salamanders

Adult male and female red-backed salamanders, Plethodon cinereus, employ "dear enemy" recognition, such that individuals are less aggressive and more submissive toward familiar territorial neighbors than toward strangers.


Having a dear enemy neighbour freed a resident to defend its territory against an intruder with similar efficiency compared to when the intruder had been the resident's only opponent.

Northern harriers on feeding territories respond more aggressively to neighbors than to floaters

  • E. Temeles
  • Environmental Science
    Behavioral Ecology and Sociobiology
  • 2004
Responses of female northern harriers Circus cyaneus on winter feeding territories towards three types of intruders (female neighbors, female floaters, and male floaters) are described and it is shown that the dear enemy phenomenon does not occur.

Aggressiveness of breeding territorial honeyeaters corresponds to seasonal changes in nectar availability

  • D. Armstrong
  • Environmental Science
    Behavioral Ecology and Sociobiology
  • 2004
Males were least aggressive when nectar was abundant, suggesting that territorial aggression could be at least partially a response to scarcity of nectar.

The effect of prey consumption on territorial defense by harriers: differential responses to neighbors versus floaters

  • E. Temeles
  • Business
    Behavioral Ecology and Sociobiology
  • 2004
SummaryFood consumption may reduce fighting intensity of territory owners by decreasing resource value (additional food cannot be consumed) and/or increasing fighting costs (food in the digestive

Territorial defence in the great tit (Parus major): Do residents always win?

  • J. Krebs
  • Biology
    Behavioral Ecology and Sociobiology
  • 2004
I removed resident pairs of great tits from their territories for short periods and released them after replacement pairs had occupied the spaces, consistent with the hypothesis that territorial residents win in contests against intruders because of an asymmetry in payoff rather than an asymmetric in resource holding potential or an arbitary convention.

The Effects of Other Fish On the Reproductive Behavior of the Male Cyprinodon Variegatus (Pisces: Cyprinodontidae)

The effects of other interacting fish should be considered when analyzing reproductive behavior, as the observation of laboratory fish in isolated pairs may produce misleading results as to the evolution and/or maintenance of behavior.