Condition explains individual variation in mobbing behavior. (22nd June 2017)

• Record Type: Journal Article
• Authors: Abolins‐Abols, Mikus; Ketterson, Ellen D.
• Editors: Koenig, W.
• Is Part Of: Ethology. Volume 123:Number 8(2017)
• Page Start: 495
• Page End: 502
• Publication Date: 2017-06-22
• Subjects: condition -- juncos -- mobbing -- predation -- risk -- social environment; Animal behavior -- Periodicals; 591.5
• DOI: 10.1111/eth.12625
• Languages: English
• ISSNs: 0179-1613

Abstract

Abstract: During mobbing, individuals approach predators with the apparent aim of reducing the risk of predation. The intensity of mobbing may depend on the costs and benefits of this behavior, which likely vary among individuals and between different social contexts. We studied whether Dark‐eyed junco male mobbing behavior is related to social environment, individual condition, and age during experimentally induced mobbing events. Based on risk‐taking theory, we predicted that individuals with high residual reproductive value—younger individuals and those in better condition—would show weaker mobbing behavior. We also expected to see weaker mobbing when the total number of individuals in the mobbing assemblage was small. All subjects were caught to assess condition and age. Focal males were then attracted to simulated mobbing events using heterospecific alarm calls. Social environment did not explain individual variation in mobbing behavior in focal juncos. Community‐wise, the relationship between the closest approach and group size was not significantly different from chance. Junco males in better condition approached the predator less closely and were less likely to give alarm calls. Age did not explain variation in mobbing. Both the mean approach and probability of giving alarm calls by junco males were repeatable, in contrast to the size and composition of mobbing assemblages in junco territories, which were inconsistent. Our results show that variation in mobbing can be linked to individual state, which likely affects the costs and benefits of mobbing.