Abstract
BackgroundIn many bird species colour traits influence social dominance and breeding success. In our study we first evaluated whether the colour of the basic plumage (tail feathers grown at the end of the breeding season), that provides an index of individual quality, influenced winter habitat use by yellow warblers. We then evaluated whether winter habitat use (inferred using δ13C and δ15N signatures of winter grown greater-coverts) influenced alternate plumage colouration, after controlling for individual quality using basic plumage colouration. Finally, we investigated whether basic and alternate plumage colouration influenced arrival dates, mate acquisition, breeding phenology and reproductive success of yellow warblers breeding in southern (Revelstoke, B.C.) and arctic (Inuvik, N.W.T.) Canada.ResultsThe colour (chroma and hue) of tail feathers, grown on the breeding grounds, was not related to subsequent winter habitat use. Greater covert and tail feather colour (chroma and hue) were correlated, suggesting genetics and/or individual quality played a role in pigment deposition. After controlling for individual difference in tail colour, δ13C values did not explain any variation in greater covert colour, but birds with high δ15N signatures had greater coverts with higher chroma. Male arrival dates varied with tail chroma in Revelstoke and tail hue in Inuvik. Males that arrived early paired with older and/or more colourful mates that initiated clutches earlier, and at one site (Revelstoke) were more likely to fledge young. In addition, in Revelstoke (but not Inuvik) males with high tail hue also acquired more colourful mates. In contrast, after controlling for individual differences in tail colour, greater covert colour did not affect male arrival date, the quality of the mate obtained or reproductive success in either population.ConclusionsOur results suggest that plumage colour effects on breeding phenology and mate acquisition result from differences in the intrinsic quality of individuals rather than a carry-over effect of winter habitat use.
Highlights
In many bird species colour traits influence social dominance and breeding success
Carry-over effects associated with access to high quality winter habitat may be generated because winter habitat influences migration and breeding phenology, but could arise because winter habitat conditions influence sexually selected plumage ornamentation involved in inter- and intra-sexual interactions on the breeding grounds (e.g. [11])
We examined whether the δ13C and δ15N signatures of greater coverts grown on the wintering grounds was related to the colour of an individual’s tail feather grown on the breeding grounds the previous summer
Summary
In many bird species colour traits influence social dominance and breeding success. In our study we first evaluated whether the colour of the basic plumage (tail feathers grown at the end of the breeding season), that provides an index of individual quality, influenced winter habitat use by yellow warblers. Study of the relationships between sexually selected plumage, winter habitat use, and breeding performance in birds that undergo moults on both breeding and wintering grounds may provide an opportunity to evaluate the relative importance of extrinsic and intrinsic factors in driving carryover effects. In these species, the colour of basic (“non-breeding”) plumage, grown on shared breeding grounds at the end of the breeding season, provides an index of individual quality that is largely independent of variation in breeding habitat [12,13]. The importance of extrinsic factors to carryover effects can be assessed by investigating how the colour of alternate plumage influences individual breeding performance after controlling for the colour of their basic plumage (Figure 1)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
