AVIS-IBIS

Birds of Indian Subcontinent

Carotenoid concentration and coloration of American Kestrels (Falco sparverius) disrupted by experimental exposure to PCBs

Publication Type:Journal Article
Year of Publication:2003
Authors:Bortolotti, GR, Fernie, KJ, Smits, JE
Journal:Functional Ecology
Volume:17
Issue:5
Date Published:2003
ISBN Number:1365-2435
Keywords:Endocrine disruption, Falco, Falco sparverius, Falco tinnunculus, Falconidae, integument coloration, plasma carotenoids, polychlorinated biphenyls, sexual selection
Abstract:Summary* 1Bright coloration in birds is typically a sexually selected trait. Expression of such traits is sensitive to environmental factors, so they can function as bioindicators of environmental contamination. Of particular value may be carotenoid-based coloration because it is commonly used as a social signal and these pigments have important health functions. * 2American Kestrels (Falco sparverius) in captivity were exposed to dietary PCBs in March. Colour and plasma carotenoids of exposed and control birds were evaluated at pairing and courtship in April, and in winter in December. Juveniles produced by these birds (exposed to PCBs only in ovo) were examined at fledging and in winter. * 3The brightly coloured ceres and lores were evaluated by comparison to colour charts and quantified using digital photographs, and plasma carotenoid concentrations were quantified by spectrophotometry. * 4During breeding, PCB-exposed kestrels differed from controls for both colour and carotenoids, although the nature of effects was sex-specific. Carotenoids of juveniles were not related to treatment at fledging. * 5In winter, PCB-exposure resulted in patterns of colour/carotenoid variation opposite to controls; exposed adult males were duller, and juveniles of both sexes were brighter, than controls. PCB juveniles had higher plasma levels of carotenoids. Sexual dimorphism was apparent in colour and carotenoids of control adults, but not for PCB-exposed birds. * 6Our results are consistent with endocrine disruption. Modulation of both colour and carotenoids may have serious consequences to social behaviour and health.
URL:http://dx.doi.org/10.1046/j.1365-2435.2003.00778.x
Short Title:Functional Ecology
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith