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
PDF in ResearchGate.net
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 – Mésange maghrébine (Cyanistes teneriffae ultramarinus), Algeria (OMAR-DZ flickr, CC-by-nc-nd license)
Bouriach, M., Samraoui, F., Souilah, R., Houma, I., Razkallah, I., Alfarhan, A. H. & Samraoui, B. (2015). Does core-periphery gradient determine breeding performance in a breeding colony of White Storks Ciconia ciconia? Acta Ornithologica 50: 149–156. doi: 10.3161/00016454AO2015.50.2.003
PDF in ResearGate.net
The timing of breeding and nest location in colonial birds may have fitness consequences. In particular, it has been demonstrated that peripheral breeders perform less well than core breeders. To determine whether environmental factors such as date of breeding and nest position influence reproductive success, we studied the breeding ecology of a large colony of White Stork Ciconia ciconia at Dréan, northeast Algeria, during 2011 and 2012. Mean egg-laying dates varied significantly between years and differed between core and peripheral nests with more precocious laying occurring in the center. Egg-laying in larger nests started earlier than in smaller ones in the core area but neither nest size nor nest position along the core-periphery gradient had any influence on studied breeding parameters i.e. clutch size, hatching success and chick productivity. There was no yearly difference in clutch size which averaged 4.7 ± 0.7 eggs (N = 156 clutches). Mean chick productivity was higher in 2012 (2.85 ± 1.21 chicks) than in 2011 (2.29 ± 2.28 chicks) and was marginally associated with egg-laying date. In contrast, nesting success declined with delayed onset of breeding. Results suggest that a low predation rate, abundant resources and a possible trade-off between fitness components may confound adaptive breeding-habitat selection in White Stork.
Young White Storks (Ciconia ciconia) at nest (Frans de Wit, CC-by-nc-nd license)
Une nouvelle zone de nidification du Flamant rose a été découverte dans l’ouest de l’Algérie par Ali Mehadji. Le site sera surveillé durant les prochains mois.
Il y a moins d’un an, une grande colonie reproductrice du Flamant rose a été découverte dans le lac Télamine, wilaya d’Oran. Voir : Le lac Télamine, nouveau site de nidification du Flamant rose Phoenicopterus roseus en Algérie (Samraoui et al. 2015).
Discovery of new breeding site of Greater Flamingo in western Algeria.
A new nesting area of Greater Flamingo was discovered in western Algeria by Ali Mehadji. The site will be monitored in the coming months. This new discovery comes less than a year after the discovery of a large breeding colony of Greater Flamingo in Lake Télamine, Oran, western Algeria.
Merci Ali pour cette bonne nouvelle!
Le nouveau site de nidification du Flamant rose (Phoenicopterus roseus) découvert dans l’ouest de l’Algérie, 20 février 2016 (Ali Mehadji).