Do female great tits (Parus major) assess males by eavesdropping? A field study using interactive song playback

Abstract

Male singing behaviour correlates with extra-pair success in several passerine birds. Singing interactions during territorial contests provide relative information on the males involved. Such information may be important in female extra-pair behaviour and eavesdropping on singing interactions among males may allow females to make such relative assessments. We used interactive playback to instigate singing contests with male great tits during the peak fertile period of their mate in an attempt to alter females' assessment of mates' quality relative to neighbours (potential extra-pair partners). We escalated a contest to one male (by overlapping his songs) and then subsequently de-escalated a contest (by alternating) to a neighbour. Intrusions onto neighbouring territories by females mated to either treatment male were then monitored. Females mated to escalation treatment males were more likely to intrude following playbacks than females mated to de-escalation treatment males. Although the absolute song output of males did not di¡er between treatments, males produced more song relative to playback in de-escalation treatments and relative song output was positively correlated with female intrusions. Therefore, female great tits eavesdrop on singing interactions and change their visitation rates to neighbouring territories according to their mate's singing performance relative to neighbours.

Computational mate choice: Theory and empirical evidence

“…Females can acquire public information on a prospective mate in two distinct ways. They may observe prospective mates in intra-sexual aggressive contests (Doutrelant and McGregor, 2000;Otter et al, 1999). For example, in female black-capped chickadees, Poecile atricapillus, the probability of extra-pair copulations depends on the outcome of male-male vocal contests.…”

Unusually extensive networks of vocal recognition in African elephants

“…The emphasis that this puts on information gathering by 'eavesdropping' has had important implications for empirical studies of male-male assessment and mate choice (e.g. Otter et al 1999). However, applying a communication networks approach to longdistance signalling also has consequences for studies of social recognition.…”

The social interaction role of song in song sparrows: implications for signal design

“…Furthermore, observations of singing in songbird neighborhoods reveal that the interactive communication is usually an ongoing process that lasts throughout the breeding season, and that birds may use direct interaction as well as eavesdropping on other interactions to continually adjust their assessment of the status of their neighbors. For example, recent field experiments on songbirds have shown that males make decisions concerning whom to challenge and females make decisions concerning whom to mate with based on information acquired by eavesdropping on singing interactions (Naguib & Todt, 1997;Otter et al, 1999;Mennill et al, 2002). In the species studied to date, song overlapping, song-type matching, frequency matching, and/or song leading seem to be some of the critical cues that indicate relative status between two singers (Mennill & Ratcliffe, 2004;Peake et al, 2005;Kunc et al, 2006).…”