Data: Direct and indirect effects of high temperatures on fledging in a cooperatively breeding bird

High temperatures and low rainfall consistently constrain reproduction in
arid-zone bird species. Understanding the mechanisms underlying this
pattern is critical for predicting how climate change will influence
population persistence and to inform conservation and management. In this
study, we analysed Southern Pied Babbler Turdoides bicolor nestling
survival, daily growth rate and adult investment behaviour during the
nestling period over three austral summer breeding seasons. High
temperatures were associated with lower body mass, shorter tarsi, and
reduced daily growth rates of nestlings. Our piecewise structural equation
models suggested that direct impacts of temperature had the strongest
influence on nestling size and daily growth rates for both 5-day-old and
11-day-old nestlings, followed by temperature-related adjustments to
provisioning rates by adults.  Rainfall and group size influenced
the behaviour of provisioning adults but did not influence nestling growth
or survival. Adjustments to adult provisioning strategies did not
compensate for direct negative effects of high air temperatures on
nestling size or daily growth rates. Detailed mechanistic data like these
allow us to model the pathways by which high temperature causes nest
failure. In turn, this could allow us to design targeted conservation
action to effectively mitigate climate effects.