Data from: Does perceived predation risk affect patterns of extra-pair paternity? A field experiment in a passerine bird

1. Non-consumptive predator effects have been shown to influence a wide
range of behavioural, life history, and morphological traits. Extra-pair
reproduction is widespread among socially monogamous birds and may incur
predation costs. Consequently, altered rates of extra-pair reproduction
are expected in circumstances characterized by increased adult perceived
predation risk. 2. Additionally, extra-pair reproduction is expected to be
most affected for birds with phenotypes that generally increase predation
risk (such as more active individuals). 3. In two consecutive years,
perceived predation risk was manipulated for great tits, Parus major
breeding in 12 nest-box plots by broadcasting sounds of their main
predator (European sparrowhawk Accipiter nisus; 6 plots). As a control
treatment, sounds of a sympatric, avian non-predator species were
broadcasted (Eurasian blackbird, Turdus merula; 6 plots). 4. Levels of
extra-pair paternity did not differ between plots with different
predation-risk treatments. Males that moved more in a novel environment
(more active or ‘faster exploring’) tended to have offspring with fewer
partners, but this effect did not vary with predation-risk treatment. 5.
From an adaptive viewpoint, predation costs associated with extra-pair
reproduction may be small and may not outweigh the benefits of extra-pair
behaviour. Research on a broader range of taxa with different mating
strategies is now needed to confirm the generality of our findings.