Does urbanisation have an impact on the trophic ecology of the Algerian hedgehog Atelerixalgirus in northern Algeria?

The Algerian hedgehog, which is an endemic Mediterranean species, is a nocturnal and terrestrial insectivorous mammal. Atelerixalgirus' populations are widespread in various habitats comprising human agglomeration, such as rural, suburban or natural ecosystems. However, the impact of the habitat's characteristics on its diet remains unknown in Algeria. To contribute to a better understanding of this question, we have analysed 158 faeces samples of the Algerian hedgehog in three different areas: urban, suburban and natural area. The findings show that the Algerian hedgehog is an opportunistic species. It feeds on several classes of Arthropoda, but the harvester ant Messorbarbarus dominates largely its menu with AR = 74.81% in the diverse habitats. Furthermore, the HAC and FCA analyses confirm the positive impact of the level of urbanisation and the anthropogenic activity on the Algerian hedgehog prey richness in the north of Algeria (79 prey species and 5574 individuals ingested in the urban area, compared to 64 prey species and 3188 individuals ingested in the natural zone).

Identification and mapping of Algerian island vegetation using high-resolution images (Pléiades and SPOT 6/7) and random forest modeling.

Despite their proximity to the coast, few studies have focused on identifying and mapping the vegetation of Algerian islands and islets. To fill this lacuna, our work, using satellite images and machine learning methods, is mainly aimed at identifying and mapping the main vegetation groups on a few islands, while evaluating the effectiveness of the random forest classifier, which is effectively used in the study of the vegetation of large areas. However, despite the high heterogeneity of their vegetation cover, the use of very high-resolution images (Pléaides and SPOT 6/7), through the fusion bands and derived bands (NDVI), has allowed the elaboration of a fairly precise vegetation map that can be used for the preparation of management and protection plans for these habitats. Our methodological approach revealed very satisfactory results, having allowed the identification of the plant communities inventoried in the field, while showing high accuracy values, ranging from 0.642 for the halophilic group of Asteriscus to 1 for the endemic Chasmophyte group of the Habibas archipelago (Pléiades images). The groups identified from SPOT 6/7 images show accuracy values between 0.67 for the Mediterranean cliff formations on Garlic Islet and 1 for the two formations (shrubby and herbaceous) of the Skikda islands. Our methodological approach, and notwithstanding the great heterogeneity and the very small surface areas of our islands and islets, has led to very satisfactory results, reflected with good overall accuracy and kappa index values (for Pléiades: overall accuracy > 92% and kappa index > 0.90; for SPOT 6/7: overall accuracy > 83% and kappa index > 0.80).

Trophic ecology of the Grey Wagtail Motacilla cinerea before and during the breeding season in the region of Bejaia (Algeria).

The diet composition of the Grey Wagtail Motacilla cinerea of the Babor Range is followed by analysis of faecal samples (90 faeces) before and during the breeding season 2010. The Grey Wagtail's diet varies depending on the stage of the breeding cycle at the southern edge of their breeding area in North Africa (Bejaia). The diet consists predominantly of aquatic preys (51.79%), with Coleoptera being the most frequent constituent (n=331, 45.5%). During the pre-laying period (February-March), the diet was variable (91 prey-taxa and H'=3,36 bits) and preys of medium size (5 to 8mm) were most common. During the incubation period (April-May), preys were mainly aquatic (60%) and larger (20 to 32mm). At the end of the breeding season (June-July), there was a greater occurrence of terrestrial preys (31 aquatic versus 30 terrestrial taxa).