INTERACTIVE EFFECTS OF INCREASED NESTBOX TEMPERATURE AND VITAMIN E ON NESTLING GROWTH ARE ATTENUATED BY PLASTICITY IN...

Area of Science:

• Avian ecology
• Environmental physiology
• Climate change biology

Background:

• Global temperatures are rising, increasing nestling exposure to heat stress.
• Heat stress during incubation can negatively affect offspring growth and survival via oxidative stress.
• Antioxidant intake may counteract detrimental effects of heat stress on developing birds.

Purpose of the Study:

• To investigate if antioxidant (vitamin E) supplementation can mitigate negative effects of increased nest temperatures on bird nestling growth and survival.
• To examine the interaction between experimental nest heating and vitamin E treatment on nestling mass.
• To assess the impact of nest heating on female incubation behavior.

Main Methods:

• Split-brood design with experimentally heated and control nests.
• Dietary vitamin E supplementation provided to half of nestlings post-hatching.
• Recording of female incubation and provisioning behaviors.
• Measurement of nestling mass as a proxy for survival and reproductive success.

Main Results:

• A significant interaction was found between nest heating and vitamin E treatment on nestling mass.
• Vitamin E supplementation increased nestling mass in heated nests but had a weak negative effect in control nests.
• Nest heating reduced female incubation investment, indicating altered maternal behavior.

Conclusions:

• Experimental nest heating effects on nestling mass can be partially mitigated by vitamin E, though effects were weak.
• Maternal incubation behavior adjusts to increased nest temperatures, potentially buffering some negative impacts.
• Female behavioral adjustments may play a role in mitigating climate change effects on bird development within certain temperature ranges.