The lingering impact of stress: brief acute glucocorticoid exposure has sustained, dose-dependent effects on reproduction

Abstract

Acutely stressful experiences can have profound and persistent effects on phenotype. Across taxa, individuals differ remarkably in their susceptibility to stress. However, the mechanistic causes of enduring stress effects, and of individual differences in stress susceptibility, are poorly understood. Here, we tested whether brief, acute increases in glucocorticoid hormones have persistent effects on phenotype, and whether effects differ according to the magnitude or duration of elevation. We used a novel method to non-invasively manipulate hormone levels on short time scales: the application of corticosterone gel to a model egg secured in the nest. Free-living female tree swallows () exposed to several brief corticosterone increases during incubation showed dose-dependent differences in behaviour throughout the reproductive period. Birds receiving treatments that simulated higher or longer acute stress responses later provisioned larger broods at lower rates; the resulting offspring were smaller in size. Treatment did not influence female body condition, oxidative stress, reproductive success or inter-annual survival, but exposed females maintained higher baseline corticosterone after treatments ceased. Overall, these results indicate that brief, acute elevations in glucocorticoids in adulthood can have long-term consequences. Furthermore, individuals that mount a greater or longer acute stress response may be more likely to experience lingering effects of stress.

Developmental temperature predicts the adult response to stressors in a free‐living passerine

“…Though we did not measure fitness in this study, the differences we found in adult CORT responses to challenges based on developmental environment could have fitness consequences. The previous work in this study population showed that females that received exogenous CORT designed to simulate higher or longer acute stress responses during incubation later provisioned at lower rates, resulting in smaller and lighter offspring (Vitousek, Taff, Ardia, et al, ). As demonstrated in this study, nestling tree swallows with lower mass can have a smaller chance of survival.…”

“…The consequences of this relationship for adult fitness are likely highly context‐specific because the relationships between CORT phenotype and fitness are complex and context‐dependent (Vitousek, Taff, Hallinger, et al, ). In this breeding population of tree swallows, there is some evidence that females with low stress responses and low baseline CORT during incubation have greater reproductive success (Vitousek, Taff, Ardia, et al, ; Vitousek, Taff, Hallinger, et al, ). Therefore, our results suggest that individuals that experienced warmer temperatures during the incubation stage of development could, in certain contexts, have increased reproductive success.…”

“…Adult females were assessed in two life‐history stages (incubation and nestling provisioning), and males were assessed during provisioning only. In females, separate models were constructed for CORT responses during incubation and provisioning because both CORT levels, and CORT‐fitness relationships, are known to differ across life‐history stages (Bonier et al, ; Kitaysky, Wingfield, & Piatt, ), including in this population (Vitousek, Taff, Ardia, et al, ). Additionally, the manner in which developmental conditions affect adult responses to challenges could also change based on the stage in the breeding cycle, as birds face different types of challenges during different stages of breeding.…”

“…Adult females were assessed in two life-history stages (incubation and nestling provisioning), and males were assessed during provisioning only. In females, separate models were constructed for CORT responses during incubation and provisioning because both CORT levels, and CORT-fitness relationships, are known to differ across life-history stages (Bonier et al, 2009;Kitaysky, Wingfield, & Piatt, 1999), including in this population (Vitousek, Taff, Ardia, et al, 2018).…”

Genome‐wide variation in DNA methylation is associated with stress resilience and plumage brightness in a wild bird

“…Predation rates are very low at our sites, but we were careful not to include any nests that failed due to predation or other known causes. One of the females categorized as “stress‐susceptible” received corticosterone doses after sample collection as part of a separate experiment, but these treatments do not increase abandonment rate in our population (Vitousek, Taff, Ardia, et al, ). Females that abandoned after receiving a handicapping treatment and females that successfully breed under benign conditions could not be placed into a resilience category and were not included in MeDIP analyses for this predictor (Figure ).…”