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Résumé :
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The various habitats attended by the white Stork (Ciconia ciconia) from January to August 1995 and the Cattle Egret (Bubulcus ibis) from November 1994 to October 1995 in the valley of Sebaou were highlighted by frequentation indexes. Direct observations on the hunting and feeding activities of these two species from March to July 1995 were also carried out. We distinguished several categories of preys according to the occupied habitats. In addition, a quantitative approach of the diet and feeding activity of these wading birds was also approached according to the seasons and of the attended trophic habitats.Within locality, the frequentation indexes of the habitats by these two species varied from one season to another according to food availability, which was function of the biological cycle of preys. The species were both very highly attracted by plowed fields. Insects largely dominated all other animal classes in the diet of both birds, but accounted only for a small part of biomass intake. Although represented by small numbers, Vertebrates represented most of all the consumed biomass. The temporal variation of the feeding effort parameters showed the highest intake values during April, nesting and breeding period for the young. These values dropped at the time when the young become independent from their parents. Feeding activity, expressed in numbers of steps, was also maximum in April, then dropped therafter. Hunting efficiency, expressed in terms of failure percentage, was maximum in summer. The variations of the feeding effort parameters according to habitats show that energy intake was highest in plowlands, and least in the mown meadows and wetland. Feeding activity, expressed in step numbers, was maximum in waste lands. Hunting efficiency, expressed in failure percentage, was maximum in ploughings and minimal in the wetlands.
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