V.G. Grinkov

Sympatric divergence and clinal variation in multiple coloration traits of Ficedula flycatchers

Geographic variation in phenotypes plays a key role in fundamental evolutionary processes such as local adaptation, population differentiation and speciation, but the selective forces behind it are rarely known. We found support for the hypothesis that geographic variation in plumage traits of the pied flycatcher Ficedula hypoleuca is explained by character displacement with the collared flycatcher Ficedula albicollis in the contact zone. The plumage traits of the pied flycatcher differed strongly from the more conspicuous collared flycatcher in a sympatric area but increased in conspicuousness with increasing distance to there. Phenotypic differentiation (PST) was higher than that in neutral genetic markers (FST), and the effect of geographic distance remained when statistically controlling for neutral genetic differentiation. This suggests that a cline created by character displacement and gene flow explains phenotypic variation across the distribution of this species. The different plumage traits of the pied flycatcher are strongly to moderately correlated, indicating that they evolve non‐independently from each other. The flycatchers provide an example of plumage patterns diverging in two species that differ in several aspects of appearance. The divergence in sympatry and convergence in allopatry in these birds provide a possibility to study the evolutionary mechanisms behind the highly divergent avian plumage patterns.

Male Colour Type and Lifetime Breeding Success in the Pied Flycatcher Ficedula hypoleuca

Abstract. The lifetime breeding success of male Pied Flycatchers was evaluated over a period of nine years (1991–99). The breeding success of males recorded in at least two breeding seasons, and nesting at least once in the study area, was analysed. The lifespan number of offspring was positively and significantly correlated with longevity. The reproductive investment in the first year of life did not correspond with longevity, and hence nonbreeding males in the first year did not compensate for the losses in fecundity. There were no differences in longevity between dark, intermediate and female-like coloured males. Darker males were less successful in their breeding attempts in the first year than paler birds. Breeding in the first year of life positively influenced the future number of fledglings, and the greater investment in reproduction in this year positively affected future brood size in dark males. Among males successfully breeding in the study area from their first season, dark males reared significantly more offspring during their lifetime, and in the first year of life, than paler ones. Nevertheless, in the total sample, lifetime brood size did not vary between differently coloured males, perhaps because dark males are more vulnerable to predators. The general difference between differently coloured males lay in how breeding efforts were distributed during life. Dark males can maximise reproductive investment from the first breeding year, while paler males increased average brood size in the following years of life only.

Delayed start of first-time breeding and non-breeders surplus in the Western Siberian population of the European Pied Flycatcher

Non-breeders are those sexually mature individuals that do not breed in a given reproductive cycle of a population. There is a widespread belief that the presence of non-breeders can affect the actual population dynamics, as well as the population responses to environmental change (Lee et al. 2017). Sternberg (1989), using demographic data, has shown that 83% and 62% of males and females, respectively, do not breed in the first year of life in the Lower Saxony (Germany) population of the European Pied Flycatcher (Ficedula hypoleuca). Later, with experimental removal of males, it has been proven that in the Lower Saxony and Moscow Region (Russia) populations, there are many non-breeding males (Sternberg et al. 2002). For the Netherlands population of the European Pied Flycatcher, the presence of a large number of non-breeders has been demonstrated using experimental removals for both males and females (Both et al. 2017). Here we have estimated the number of non-breeders in the Western Siberian population of the European Pied Flycatcher using demographic data (11 cohorts from 2001 to 2011 of birth) and experimental removal of males. We have shown that both males and females can start to breed at the age of one to five years. The proportion of non-breeders can be 59.5% and 68.5% for first-year males and females, respectively. We discuss the differences in the proportion of non-breeders between the Western Siberian and European populations of the European Pied Flycatcher, as well as factors affecting the number of non-breeders. Session # P13 - Population and Individual Ecology Poster Number P13.009 How to cite the abstract Grinkov, V. G. & H. Sternberg (2018). Delayed start of first-time breeding and non-breeders surplus in the Western Siberian population of the European Pied Flycatcher. 27th International Ornithological Congress, Vancouver, Canada, August 19-26, 2018. P13.009 How to cite the poster Grinkov, V. G. & H. Sternberg (2018). Delayed start of first-time breeding and non-breeders surplus in the Western Siberian population of the European Pied Flycatcher. bioRxiv 387829; doi: https://doi.org/10.1101/387829