DOI: 10.5061/dryad.3r2280gv1
title: Roadkill risk in European birds: The role of detection and plumage colouration

description: Wildlife-vehicle collisions (WVCs) are a significant cause of mortality
 among European birds. This poses a threat to the conservation of birds
 because pervasive human-related structures, such as road networks, are
 expected to expand over the continent in the next few decades. For this
 reason, a good understanding of the traits that make a bird species more
 vulnerable to being killed through a collision with a vehicle is
 essential. Traits such as body mass, plumage colouration, boldness, and
 behavioural characteristics can shape roadkill risks. Here, we first
 tested the presence of a phylogenetic signal in the roadkill rate of a
 pool of 55 European birds. Then, we explored the potential correlation
 between roadkill rate and several ecological characteristics of species.
 Overall, the incidence of casualties among bird species does not covary
 with phylogeny. Territoriality, body size, migratory strategy and diet
 were not significantly associated with roadkill rates in European birds.
 However, we found that more conspicuous birds and species characterised by
 a high percentage of dark brown colouration in their plumage were more
 affected by roadkill. The colour combinations brown dark with brown light
 and brown dark with grey dark seem less associated with higher roadkill
 rates. No correlation was found between roadkill rate and single-colour
 dominance (e.g., a high colour inequality) in European birds. Our findings
 suggest that a) species exhibiting more boldness and less shyness against
 humans (e.g., easier to be detected) are also species overall more active
 and consequently more likely to collide with vehicles on the roads, and b)
 some colours could play a role in the risk assessment of WVC for birds.
description: # Roadkill risk in European birds: The role of detection and plumage
 colouration Dataset DOI:
 [10.5061/dryad.3r2280gv1](10.5061/dryad.3r2280gv1) ## Description of the
 data and file structure Dataset with ecological characteristics of birds,
 roadkill rate, and plumage colouration as described in Delhey et al. 2023.
 ### Files and variables #### File:
 dataset_Morelli_Benedetti_2025_roadkill_and_colours.csv **Description:** 
 ##### Variables Variable Detail Source Species: Species name
 [https://doi.org/10.1890/13-1917.1](https://doi.org/10.1890/13-1917.1)
 Common name: English name
 [https://doi.org/10.1890/13-1917.1](https://doi.org/10.1890/13-1917.1)
 Roadkill rate: Roadkill rate corrected is the number of individuals killed
 per kilometre of road per year for each species, corrected by accounting
 for the carcass persistence probability
 [https://doi.org/10.1002/fee.2216](https://doi.org/10.1002/fee.2216)
 IUCN.category: Extinct (EX), Extinct in the Wild (EW), Critically
 Endangered (CR), Endangered (EN), Vulnerable (VU), Near Threatened (NT),
 Least Concern (LC), or Data Deficient (DD)
 [https://www.iucnredlist.org/](https://www.iucnredlist.org/) Detection
 rate: level of detectability of the given species in areas where their
 occurrence was first confirmed
 [https://doi.org/10.3389/fevo.2021.671492](https://doi.org/10.3389/fevo.2021.671492) Body mass (g): body mass in grams [https://doi.org/10.1890/13-1917.1](https://doi.org/10.1890/13-1917.1) Diet: main type of diet preference is classified into the following categories: granivorous, granivorous-insectivorous, insectivorous, and omnivorous/scavenger [https://doi.org/10.1890/13-1917.1](https://doi.org/10.1890/13-1917.1) Family: family [https://www.iucnredlist.org/](https://www.iucnredlist.org/) Order: order [https://www.iucnredlist.org/](https://www.iucnredlist.org/) black_36_34_31: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) blue.dark_58_81_126: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) blue.light_118_156_200: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) brown.dark_108_89_54: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) brown.light_171_148_95: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) green.dark_56_98_48: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) green.light_138_172_81: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) grey.dark_90_85_80: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) grey.light_153_150_143: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) purple.dark_86_61_123: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) purple.light_192_139_179: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) red.dark_161_51_37: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) red.light_225_113_80: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) rufous.dark_131_71_46: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) rufous.light_200_128_80: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) white_229_228_223: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) yellow_229_211_134: proportion of the body covered by each human-visible colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) Territoriality: non-territorial, weakly territorial or territorial [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) Migration strategy: resident, partially migrant, strict migrant [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) Colouration inequality: (Gini index), Gini inequality index applied to all columns with the relative proportion of colours 1st dominant colour: colour covering the largest proportion of the body [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) 2nd dominant colour: second colour covering a larger proportion of the body [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) 3rd dominant colour: third colour covering a larger proportion of the body [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) Dominant colours combination (two levels): combination of 1st dominant colour and 2nd dominant colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) Dominant colours combination (three levels): combination of 1st dominant colour, 2nd dominant colour and 3rd dominant colour [https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212](https://doi-org.infozdroje.czu.cz/10.1073/pnas.221769212) ## Code/software No specific code was generated. ## Access information Data was derived from the following sources: * Data on plumage colouration was The data about bird species colouration were published by Delhey et al. 2023 and is publicly available at this link: [https://www.pnas.org/doi/10.1073/pnas.2217692120#supplementary-materials](https://www.pnas.org/doi/10.1073/pnas.2217692120#supplementary-materials) Delhey, K., Valcu, M., Muck, C., Dale, J., & Kempenaers, B. (2023). Evolutionary predictors of the specific colors of birds. Proceedings of the National Academy of Sciences, 120(34), e2217692120. [https://doi.org/10.1073/pnas.2217692120](https://doi.org/10.1073/pnas.2217692120)