The effects of preen oils and soiling on the UV–visible reflectance of carotenoid-pigmented feathers
Plumage coloration, particularly when carotenoid-based, is important in social signaling in birds. Although feather color is a relatively stable trait, individuals may modify it with >cosmetic> substances such as preen oils. In addition, dirt accumulation may influence plumage coloration and f...
| Published in: | Behavioral Ecology and Sociobiology |
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| Main Authors: | , , |
| Other Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
Springer
2011
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| Subjects: | |
| Online Access: | http://hdl.handle.net/10261/143995 https://doi.org/10.1007/s00265-011-1153-y https://doi.org/10.13039/501100004837 https://doi.org/10.13039/501100000038 https://doi.org/10.13039/501100011698 |
| Summary: | Plumage coloration, particularly when carotenoid-based, is important in social signaling in birds. Although feather color is a relatively stable trait, individuals may modify it with >cosmetic> substances such as preen oils. In addition, dirt accumulation may influence plumage coloration and further affect signal perception by receivers. Here, we analyze the separate potential effects of preen oils and soil accumulation on the reflectance properties of carotenoid-pigmented feathers across the visual range of most bird species, which includes the ultraviolet (UV). Using the yellow portion of tail feathers of Bohemian waxwings (Bombycilla garrulus), we performed two separate experiments where: (a) preen oils and/or soil were removed, or (b) preen oils (from black-billed magpies Pica pica or eagle owls Bubo bubo) were added. Preen oil addition reduced brightness but increased UV hue and yellow chroma. UV chroma was reduced by the addition of magpie (but not owl) preen oil. Soil accumulation had little effect on plumage reflectance in the UV range but significantly reduced yellow chroma. According to models of avian vision, both of these effects are detectable by birds and biologically meaningful when compared with natural variation between the sexes and age classes. We conclude that preen oil and soil accumulation can significantly affect the UV-visible reflectance of carotenoid-based plumages. As such traits typically advertise individual quality, preening and soiling have the potential to modify the information content of carotenoid-based plumage traits and how these signals are perceived by receivers. L. P.-R. was supported by a postdoctoral contract (07/028-A) from Junta de Comunidades de Castilla-La Mancha (JCCM) and a “Juan de la Cierva” contract from the Spanish Ministerio de Ciencia e Innovación (MICINN). Funding was also provided by Natural Sciences and Engineering Research Council of Canada and the Stuart and Mary Houston Professorship in Ornithology (to G. R. B). Peer Reviewed |
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