Characterizing genetic diversity and structure of populations is essential for the effective conservation of threatened species. Orchis patens sensu lato is a narrowly distributed tetraploid species with a disjunct distribution (i.e., Northern Italy, North Africa and the Canary Islands), which is facing a severe decline. In this study, we evaluated levels of genetic diversity and population structuring using 12 new nuclear microsatellite markers. Our analyses of genetic differentiation based on multiple approaches (Structure analysis, PCA analysis, and F-statistics using the ploidy-independent Rho-index) showed that gene flow is low across the range of O. patens s.l., particularly in the Canary Islands. Clear differences in allele frequencies between Italy, Algeria and the Canary Islands underlie the genetic differentiation retrieved. Our study provides support for the recognition of O. canariensis as a sister species to O. patens and the separation of the Italian populations as a new subspecies of O. patens. Despite the high heterozygosity values found in all populations (ranging from 0.4 to 0.7), compatible with the tetraploid status of the species, small population sizes and reduced gene flow will be likely detrimental for the different populations in the long term, and we recommend immediate conservation actions to counteract further fragmentation and population decline.

Le romarin (Rosmarinus officinalis)est une espèce très abondante dans la région de Hammamet de la wilaya de Tébessa à l'Est algérien, il est utilisé en médecine populaire, cosmétique et phytopharmacie. L’extraction des huiles essentielles du romarin a été effectuée par entraînement à la vapeur d’eau. L’étude chimique de ces huiles essentielles par CPG-SM a révélé la richesse de ces dernières en 1,8 cinéole par rapport aux autres composés. L’activité des huiles essentielles de Rosmarinus officinalis sur trois souches bactériennes pathogènes (Staphylococcus aureus, Escherichia coli, Acinetobacter sp.) par la technique d’aromatogramme montre que le pouvoir antimicrobien de ces huiles est très important et se caractérise par une action bactéricide contre les germes suscités.

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telailia S., Boutabia L., khemis El-Hak M.D., Elafri a., Djebbari n.: Multi-annual and seasonal patterns of waterbird assemblages in a Mediterranean coastal lagoon (El Mellah lagoon) of northeastern algeria. Ekológia (Bratislava), vol. 36, no. 2, p. 146-158 , 2017. recently, Mediterranean coastal lagoons have raised considerable environmental concerns. Long-term studies of seasonal changes in waterbird assemblages are therefore extremely important in terms of ecological relevance and conservation of these sensitive ecosystems. an ornithological survey of four years was carried out in a typical costal wetland (El Mellah lagoon) of northeastern algeria. intra-seasonal comparison of waterbird assemblages (diversity indices) demonstrates clear changes between the wintering and the breeding periods. it seems that the first one was rich in term of species number than the second season (43 against 24). in contrast, the breeding seasons were more equilibrate (high values of Simpson, Shannon and evenness index). additionally, curves in the diversity/dominance diagram revealed that both wintering and breeding assemblages share the same characteristics of community structure, few dominant species (with intermediate relative abundance) and many rare species with the relative abundance lower than 0.1. invertebrates (25 species) and piscivorous (11 species) are the most abundant guilds over the four years of study (no significant differences among years have been calculated). The marked decline in bird species diversity recorded in this study (in comparison with previous studies) is mainly due to salinity oscillations (due to aquaculture activities) and may be of concern to wetland managers and it might be useful to provide some guidelines about the characteristics that coastal lagoons have to follow in the construction process to enhance the biodiversity.

Birds constitute a zoological group which is considered to be a good indicator of balance and biological diversity. The aim of this study was to investigate the birds of the region on Tamanresset which is situated in the south of Algeria and has an area of 554.000 km2. Direct observations with camera and a pair of binoculars, supported by ornithological surveys carried out by progressive frequently sampling, in each stations of study area, 44 bird species were observed in this region which fall into 12 orders and 24 families. Among these species, 3 new observations recorded for the 1st time belonging to White-rumped Seedeater (Crithagra leucopygia) and blue-napped mousebird (Urocolius macrourus) along with 2 other species, the rose-ringed parakeet (Psittacula krameri) and the African silver bill (Euodice cantans), are listed as an expansion in this region.

Understanding the factors affecting escape behaviour in waterbirds can be useful in the management of human disturbances. A common measure of escape response is flight initiation distance (FID), the distance at which an approaching intruder disturbs an individual bird enough to make it move away. Here, we analyse the escape behaviour of a set of waterbirds for the first time within a North African context. We tested (one-way ANOVA and general linear model) how FID varied with the area where waterbirds were temporal scale, distance at which the observer start approaching to the sampled birds, body size, flock size, species composition of the flock and foraging activity of the sampled birds. We collected 866 individual FIDs for 19 waterbird species wintering at two north Algerian wetlands (the Mekhada marsh, RAMSAR site, El-taref District and the Sebkhet El-Mahmel, unprotected wetland, Khenchela District). The obtained FIDs ranged from 32.6 m in smaller species as the Kentish plover Charadrius alexandrines to 167 m in larger ones as the ruddy shelduck Tadorna ferruginea. The obtained models stated that differences in the absolute levels of FIDs were mostly related to starting distance (Effect size = 0.62), to which is added a relatively little effect of wetland status, taxonomic differences, temporal scale, body size, flock size, species composition of the flock and bird activity. More specifically, FID was lower in smaller and homospecific groups at early winter in the protected wetland. Reserve managers in North Africa could use species and context-specific FIDs in delineating appropriate buffer areas and in the design of management initiatives aimed at minimising eventual potential threat due to human disturbance and guaranteeing animal welfare and wildlife.

The Algerian coastline, known for its diverse array of fauna primarily dependent on marine ecosystems, has recently experienced notable changes in its community, perhaps due to the severe weather conditions in the North Atlantic. To explore this phenomenon, we conducted an extensive survey of the entire Algerian coast, specifically focusing on fishing ports and beaches, during November and December of 2022. Our objective was to investigate the remarkable and recent irruption of the razorbill Alca torda, which typically spends the winter in the open sea. Throughout our study, we documented a total of 32 sightings of razorbill individuals, including both live specimens observed within harbors (as depicted in Fig. 2 & 3) and deceased individuals washed up on the beaches.

Les auteurs signalent une observation de Pteris vittata L. dans la Numidie algérienne. Cette découverte permet de faire le point sur sa répartition en Algérie.