Organisation spatio-temporelle de la reproduction chez le Moineau espagnol Passer hispaniolensis en zone semi-aride
1986
Metzmacher, Maxime
Nests supports are made atractive on a high-perched position as far as the Spanish sparrow is concerned. Such supports should be closely-packed, provided with a plethora of sprigs and located near cereal fields. The breeding colonies of early clutches that gather several thousands of birds in Orania are comparatively independant of aquatic areas. High density nest zones within a colony of birds seem to be related not only to the supports themselves but also to the diversified vegetal environment. Simultaneous species reproduction in the Oran area is carried out in each region accordingly. Futhermore, results reveal that the reproduction may be of itinerant character, therefore tallying with Ward's assumption that among seed-eating species living in semi-arid zones, the Red-billed quelea cannot de regarded as the solely itinerant breeder. Although clutch size can vary from various sectors within the framework of a colony, homogeneity is maintained inside the region itself. However, the number of young fledged can be otherwise. On the other hand, few sparrows will exceed one single clutch in seasonal dry weather in the surveyed area. Discussions on the various results obtained are mainly looked upon in line with space/time fluctuations of the food supply and parental behaviour. In other respects, heterogeneity of brood success indicate that the Spanish sparrow has no apparent mechanism for colony-size regulation. While nests are being built, colony-size however can be relevant to habitat restraints. Attempts at giving theorical model of the foregoing are still being made.
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