title: Parental food provisioning is related to nestling stress response in wild great tit nestlings: implications for the development of personality.
abstract: BACKGROUND
  Variation in early nutrition is known to play an important role in shaping the behavioural development of individuals. Parental prey selection may have long-lasting behavioural influences. In birds foraging on arthropods, for instance, the specific prey types, e.g. spiders and caterpillars, matter as they have different levels of taurine which may have an effect on personality development. Here we investigated how naturally occurring variation in the amounts of spiders and caterpillars, provisioned to nestlings at day 4 and 8 after hatching, is related to the response to handling stress in a wild passerine, the great tit (Parus major). Broods were cross-fostered in a split-brood design allowing us to separate maternal and genetic effects from early rearing effects. Adult provisioning behaviour was monitored on day four and day eight after hatching using video recordings. Individual nestlings were subjected to a handling stress test at an age of 14 days, which is a validated proxy for exploratory behaviour as an adult.
  
  
  RESULTS
  Variation in handling stress was mainly determined by the rearing environment. We show that, contrary to our predictions, not the amount of spider biomass, but the amount of caterpillar biomass delivered per nestling significantly affected individual performance in the stress test. Chicks provisioned with lower amounts of caterpillars exhibited a stronger stress response, reflecting faster exploratory behaviour later on in life, than individuals who received larger amounts of caterpillars.
  
  
  CONCLUSIONS
  These results suggest that natural variation in parental behaviour in wild birds modulates the developmental trajectories of their offspring's personality via food provisioning. Since parental provisioning behaviour might also reflect the local environmental conditions, provisioning behaviour may influence how nestlings respond to these local environmental conditions.
authors.affiliation: Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.
authors.forename: Kees van
authors.initials: Kv
authors.lastname: Oers
authors.affiliation: Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands; current address: Department of Psychological and Brain Sciences, Indiana University, Bloomington IN, USA.
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Kohn
authors.affiliation: Behavioural Ecology Group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands.
authors.forename: Camilla A
authors.initials: CA
authors.lastname: Hinde
authors.affiliation: Behavioural Ecology Group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands.
authors.forename: Marc
authors.initials: M
authors.lastname: Naguib
keywords: Animal personality; Caterpillars; Early development; Food type; Great tit; Parental feeding; Spiders; Stress response; Taurine