Avian diversity is used to assess the functionality of diverse types of habitats around Salt Lake Djendli, Northeast Algeria. The landscape is stratified into five habitat types in a gradient from wetland to forested mountains. Bird species found in these habitats can be classified into four ecological groups with decreasing degrees of aquatic specialisation and increasing forest specialisation. For each surveyed species, five ecological status were assigned. Overall, there was lower species richness in urban areas compared to other "natural" habitats. Birds have a biogeographical affinity to the western Palaearctic according to the dominant faunal types. Interactions of ecological status with phenological traits reveal that water birds are different from non-aquatic species because most of them are migrants. Moreover, overall, there is no worrying conservation status for surveyed birds. Bird diet is dependent on the ecological status that differentiate bird groups from each other due to differences in the food resources of the habitats they frequent. Phenological categories tend to link together birds of urban and open-lands. These two groups are affected by seasonal human activities. Our findings emphasise the importance of using combinations within the birds' ecological status, which would give information on the actual state of avifauna. This approach is relevant for future programmes and conservation actions.

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Background: The Shelduck (Tadorna tadorna) is a characteristic waterbird species of inland wetlands in northeastern Algeria. Its wintering behavior in relation to changes of local abundances and foraging group density is poorly known. Objectives: This study aims at monitoring patterns of diurnal activities and the variation of behavioral time-budgets in relation to numbers of wintering Shelducks. We investigate temporal variations of diurnal activities across multipletime scales and consider their interrelationships. Methods: Assessments of local population abundance were weekly surveyed during two wintering seasons (2010-2012), whereas diurnal activities (feeding, sleeping, swimming, preening, loafing, flying, courtship, and antagonism) were studied three times a month during seven hours (08:00-16:00) using the Scan method. Time budget variations of each behavioral activity were tested using nested ANOVAs following multiple time scales. Generalized linear mixedeffects models (GLMM) tested whether variations in diurnal activities were density-dependent. Results: During the wintering season, Shelduck's numbers followed a bell-shaped trend, which indicated that the species was typically a wintering migrant in Sabkha Djendli. The first individuals arrived onsite in October-November then numbers reached a peak in January (up to 2400 individuals in 2012) with steady density during December-February, afterward individuals left the site progressively until late April when the site is deserted. During both wintering seasons, diurnal activities were dominated by feeding (60%), followed by sleeping (12%) then swimming and preening with 9% and 8%, respectively. The rest of the activities (loafing, flying, courtship and antagonistic behaviors) had low proportions of time budget. ANOVAs showed that activity time budgets varied significantly following multiple time scales (year, season, month, day, semi-hour). Time budgets of diurnal activities during each wintering season were significantly interrelated. Correlations patterns between the two seasons were similar. GLMMs revealed that the variations of diurnal activities were not density-dependent, except for preening and swimming. Conclusion: During the wintering season, habitats of Sabkha Djendli are important for waterbirds, including the Shelduck that used the lake mainly for food-foraging and resting. The 2400 individuals censused in midwinter are important locally and at the North African scale. This stresses the need to strengthen the protection status of this wetland and mitigate degradation sources that threaten wintering waterfowl.