Breeding ecology of African Blue Tits on the periphery of species range

Kouidri, M., Adamou, A.-E., Bańbura, A., Ouakid, M. L., Chabi, Y. & Bańbura, J. (2015). High egg size variation in African Blue Tits Cyanistes caeruleus ultramarinus on the periphery of species range. Acta Ornithologica 50: 205–212. doi: 10.3161/00016454AO2015.50.2.008
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Abstract:

Amount and quality of resources may be variable and generally poor in habitats of marginal avian populations living at the edge of species breeding range. We studied variation in egg traits (length, breadth, volume and shape) in three populations of the African Blue Tit Cyanistes caeruleus ultramarinus inhabiting degraded habitats in highlands of Algerian Saharan Atlas at mean altitudes 1328–1437 m a.s.l. We found high within-clutch repeatability of all the egg traits studied. As theoretically expected in peripheral parts of the species geographic range, there was considerable variation in egg-size traits among the study populations, with eggs being distinctly smaller and more elongated at a site characterised by most human-modified habitat composed of maquis scrubland with rare Pistacia trees. Egg length and shape tended to be affected by the altitude of nest site and by clutch size, but not laying date. We found some effects of egg traits on hatching and fledging success, suggesting that fitness advantage of egg sizes is dependent of egg shape. We conclude that the above patterns of variation in egg size and shape of the African Blue Tit populations have influence of fitness. Our finding of considerable variation in egg traits between separate peripheral populations confirms the theoretical expectation and seems to be a novel result.

African Blue Tit (Cyanistes teneriffae ultramarinus), Algeria

African Blue Tit – Mésange maghrébine (Cyanistes teneriffae ultramarinus), Algeria (OMAR-DZ flickr, CC-by-nc-nd license)

 

Breeding performance of blue tits in relation to lead pollution and nest failure rates in Algeria

Brahmia, Z., Scheifler, R., Crini, N., Maas, S., Giraudoux, P., & Benyacoub, S. (2013). Breeding performance of blue tits (Cyanistes cæruleus ultramarinus) in relation to lead pollution and nest failure rates in rural, intermediate, and urban sites in Algeria. Environmental Pollution 174: 171-178.

Abstract:

The breeding parameters and the egg and nestling morphology of Cyanistes caeruleus populations from rural, intermediate, and urban sites in Algeria and the relationships of those variables with lead contamination were studied during three consecutive years. Breeding success was explained only by predation and vandalism rates. Predation was higher in the rural area, whereas vandalism was higher in the urban site. The other measured breeding parameters and egg characteristics were relatively insensitive to study site. The morphology of urban nestlings exhibited a trend toward smaller body size and mass compared to individuals from intermediate and rural sites. Although lead concentrations were higher in the tissues of urban birds than in intermediate and rural individuals, we did not detect a clear influence of this variable on nestling morphology. We conclude that urbanization influenced blue tit breeding parameters through predation and vandalism and nestling morphology through mechanisms other than lead pollution.

Highlights:

► Life history traits in relation to lead contamination were studied in blue tits from rural, industrial and urban sites.

► The study took place in Annaba, the fourth most populated city of Algeria, during 3 consecutive years.

► Breeding success depended on predation and vandalism, which were high in the rural and urban sites, respectively.

► Urban nestlings exhibited a trend toward smaller body size and mass, which was not explained by lead contamination.

► Urbanization influences breeding success and nestling morphology in blue tits through other mechanisms than lead pollution.