Thu, Aug 18, 2022: 5:00 PM-6:30 PM
ESA Exhibit Hall
Background/Question/Methods: Environmental factors, such as elevated temperature, can have varying effects on animal fitness. Environmental temperature early in life can have profound effects on survival but also might have lasting effects into adulthood. Although studies have found an effect of early-life temperature on hosts, few of these studies focus on wild animals. The goal of this study is to determine the early-life effects of elevated temperature on nestling bird health and survival. Specifically, we experimentally increased temperature in the nests of Eastern bluebirds (Sialia sialis) during the first week of the nestling period and then quantified nestling morphometrics and survival.
Results/Conclusions: Our experimental treatment increased nest temperature by approximately 5 degrees. Nestlings in nests with elevated temperatures had lower body mass and smaller first primary feathers. One explanation for this result could be that nestlings devoted more energy to maintaining an optimal body temperature and less energy toward growth pathways relating to first primary feather growth and mass gain. In contrast to our body measurements, temperature treatment did not affect nestling survival. Our study demonstrated that early-life elevated temperatures have a sublethal, but not a lethal, effect on birds. These results suggest that although nestling birds survive elevated nest temperatures, they may experience lasting effects of heat stress after they leave the nest. We will also discuss the lasting implications of early-life heat stress on later-life health.
Results/Conclusions: Our experimental treatment increased nest temperature by approximately 5 degrees. Nestlings in nests with elevated temperatures had lower body mass and smaller first primary feathers. One explanation for this result could be that nestlings devoted more energy to maintaining an optimal body temperature and less energy toward growth pathways relating to first primary feather growth and mass gain. In contrast to our body measurements, temperature treatment did not affect nestling survival. Our study demonstrated that early-life elevated temperatures have a sublethal, but not a lethal, effect on birds. These results suggest that although nestling birds survive elevated nest temperatures, they may experience lasting effects of heat stress after they leave the nest. We will also discuss the lasting implications of early-life heat stress on later-life health.