Individual optimization of reproductive investment and the cost of incubation in a wild songbird

Despite avid interest in life-history trade-offs and the costs of reproduction, evidence that increased parental allocation reduces subsequent breeding productivity is mixed. This uncertainty may be attributable to environmental heterogeneity in space and time, necessitating experiments across a range of ecological contexts. Over three breeding seasons, we cross-fostered clutches between nests to manipulate incubation duration in a wild population of Carolina wrens, a species in which only females incubate, to test for a cost of incubation on current and future reproduction. Prolonged incubation affected maternal productivity in a manner dependent upon the current environment and initial investment in eggs, suggesting incubation is optimized according to other components of reproduction and individual quality. Effects of incubation duration on foster-nestling condition varied between years, being costly in one, beneficial in another, and neutral in the third. The proportion of young fle..., Data were collected from wild Carolina wrens (Thryothorus ludovicianus) breeding at the Edward J. Meeman Biological field station in southwest TN, USA.
Data were standardized using z-scores and analyzed using SAS v. 9.4 (more info can be found in the attached Statistical Code and README files). , , Individual optimization of reproductive investment and the cost of incubation in a wild songbird. (2023). The American Naturalist.

Authors: Kelly D. Miller*, Ashley J. Atkins Coleman, Kelly L. O'Neil, Alexander J. Mueller, Rin D. Pell, and E. Keith Bowers

*corresponding author ([e-mail])

***Dataset published to Dryad updated Dec. 2023 after an error was discovered - one nest was included in the originally-published dataset which had been excluded from analyses due to partial-brood depredation (only 1 nestling remained, which invariably affected measures of parental investment).

All authors assisted with data collection. K.D. Miller and E.K. Bowers wrote the statistical code.

This study examined the life-history costs of incubation over three years via a manipulation of its duration. The costliness of incubation varied within and between years, being entirely dependent on environmental conditions and maternal quality.

The data collected for this experiment at the Meema...