Population Dynamics and Distribution Patterns of Diurnal Raptors in Northeastern Algeria: Seasonal Variation and Some Nesting Characteristics

Abstract

Providing a live data monitoring of raptor abundances and spatial localization of their most important nesting areas is very helpful in building a strong future study and applying a sound strategy for effective safeguarding of these emblematic species. Using geographic information system (GIS) and global positioning system (GPS) techniques, we investigated spatial patterns of raptors distribution in the northeastern areas of Algeria during two consecutive breeding seasons (2014 and 2015). The total area sampled (31,000 km2) host diverse raptor species (14 species), among them, the threatened species Egyptian vulture (Neophron percnopterus; 108 individuals and 19 active nests) and red-footed falcon (Falco vespertinus; 12individuals). The value of the region is attested by the presence of an abundant population of nesting black kite (Milvus migrans; 337 individuals). The large-scale spatial analyses of the studied region illustrate certain similarities in nesting habitat selection among raptors. Almost all species (90% of 209 nests detected) preferred to nest within multispecies assemblages (20 raptor assemblages found) and occupied altitudinal rocky cliffs across the inland region (semi-arid zones) rather than coastal region (sub-humid zones). Among all raptor species, exclusively, the common kestrel (Falco tinnunculus) is relatively synanthropic, because it was found to breed within cities (tolerate human activities). The raptor community in the coastal versus inland regions differed by 14%. The latter area seems to be more preferred in nest building, probably consequence of their semi-arid bioclimatic and landscapes characteristics, where high elevations and grasslands forming mosaics with Oak, Alpine, and Cedar forests are patchily distributed. The study is a first mapping database of important nesting sites dispatched across the northeastern areas of Algeria, and it can be effectively used in future complementary researches that aim to elucidate environmental factors that affect raptors life cycle.

Keywords

• raptor assemblages
• cliff nesting
• roadside point transect
• inland regions
• gis