Heavy metal pollution exposure affects egg coloration but not male provisioning effort in the pied flycatcher Ficedula hypoleuca

Heavy metal pollution is known to negatively affect numerous traits in birds, including foraging, metabolism, immunity, and reproductive success. In this study, our primary aim was to assess the impact of metal pollution exposure on the visual appearance of the pied flycatcher (Ficedula hypoleuca) eggs. Specifically, we focused on blue-green biliverdin-based coloration, a trait expected to function as a signal of female quality to males. In line with the sexually selected egg coloration (SSEC) hypothesis, which posits that males respond to more intensely colored eggs by increasing their provisioning effort, our second objective was to investigate whether metal pollution exposure affects this specific signaling mechanism and subsequent male behavior. Our results showed that although coloration did not correlate with female quality or male provisioning effort, egg blue-green coloration decreased in polluted areas compared to non-polluted control areas. Our analysis of reflectance data rev..., , , ## Heavy metal pollution exposure affects egg coloration but not male provisioning effort in the pied flycatcher *Ficedula hypoleuca*

[https://doi.org/10.5061/dryad.2280gb61k](https://doi.org/10.5061/dryad.2280gb61k)

Mari *et al.*, Journal of Avian biology, 2024

Paper DOI: 10.1111/jav.03283

### Description of the data and file structure

#### FILE 1. Pied\_flycatcher\_egg\_coloration.txt

This file contains raw coloration data for 458 flycatcher eggs, including reflectance at four image channels and cone caches obtained from photographies (refer to methods for details). This dataset was used to calculate coloration-related variables included in other datasets such as blue-green chroma and blue-green consistency (SD of chroma). Formulas are detailed in the methods. The variables are:

* Label: ID number of nestbox and egg number separated by an underscore
* bg_lum: luminance (brightness)
* bg_lw: photon-catch values for long-wavelength-sensitive cone

* bg_mw: photon-catch ...