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The autochthonous caramote prawn, Penaeus kerathurus, is highly exploited and widely studied throughout its distribution range in the Mediterranean. However, in Algeria, very few studies have been conducted on its biological aspects. In this research article, we provided for the first time a detailed analysis of the key parameters: length-weight relationships (LWRs) and condition factor (K) of prawns harvested from the unique coastal lagoon in the country, El Mellah Lake. Thus, the morphometric relationships between the total and carapace lengths against body weight were established for 1066 males, 608 females, and grouped individuals, revealing a negative allometric growth in all cases. Similarly, all K-obtained average values were less than the unit, indicating the poor nutritional status of prawns. Overall, the present findings showed that both parameters were sex-dependent and more likely reflect the population response to species growth and reproductive traits, biotic (new predator-prey relationship), and abiotic (lagoon’s meso-oligotrophic status) stimuli. The present study will be useful for better enhancing our understanding about P. kerathurus in southwestern Mediterranean and lagoon habitats. [ABSTRACT FROM AUTHOR]

The Maghreb magpie (Pica mauritanica) is an endemic bird to North Africa, encompassing Algeria, Morocco, and Tunisia. Unfortunately, its population is facing a significant decline primarily attributed to habitat loss and fragmentation resulting from urbanization and agricultural practices. Due to the lack of large-scale studies on habitat requirements of Pica mauritanica, investigating the habitat preferences of this species and understanding the potential threats remain crucial for effective conservation strategies. We performed species distribution model (SDM), incorporating both occurrence records and predictor variables, to investigate the potentially suitable habitat and the factors influencing the distribution of the Maghreb magpie (Pica mauritanica) in North Africa. Among the environmental predictors examined, the enhanced vegetation index (EVI), elevation, and human settlement have been identified as key factors influencing habitat suitability. Specifically, EVI and human settlements positively contribute to suitability, while precipitation and temperature exert negative effects. The SDM results were consistent with our field observations, indicating that Pica mauritanica tends to avoid urban settlements or densely forested regions, thus preferring village farm areas, especially during the breeding period. The model forecasts high habitat suitability for Pica mauritanica along the eastern coastal regions of Tunisia, the western coastal areas and the High Atlas Mountain range of Morocco, as well as the Hautes Plaines region in Algeria, with a fragmented patch pattern. To ensure the sustainable survival of Pica mauritanica, we endorse the preservation of traditional farming practices, where farmland birds are mainly impacted by agricultural intensification and land use changes. Further extensive studies are needed to determine population size and explore habitat requirements at a micro-scale to guide conservation priorities. [ABSTRACT FROM AUTHOR]

The Chinese pond mussel Sinanodonta woodiana (Lea, 1834) (Bivalvia: Unionidae) is among the most invasive freshwater species worldwide. The last decades have seen its rapid geographical spread beyond the species' natural range, particularly in anthropogenically modified water bodies across Asia, America, and Europe where it is now very common. In this paper, we also confirm the presence of S. woodiana in Africa (Algeria) by establishing the UNESCO Biosphere Reserve and Ramsar site Oubeira Lake as a new locality for its occurrence. In all likelihood, S. woodiana was accidentally introduced in the 1980s with Asian fish species imported from Hungary for stocking purposes. The present survey was conducted in the summer of 2020, and here we present the first data on several biological aspects of 141 S. woodiana specimens collected in the lake fringe area. The age structure varied from two to over height years old; medium- and large-sized individuals with shell lengths ranging from 102.23 to 183.55 cm accounted for 96% of sampled mussels. A study of the conchological features revealed that bivalves adopt the species' typical morphological trends. Overall, our findings showed that S. woodiana succeeded in establishing a viable population in Oubeira Lake, which allows for the assumption that additional records can be predicted at a regional scale in locations related to the lake water system in Algeria and Tunisia. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to provide for the first time data on a hard substratum macroinvertebrate species inhabiting El Mellah, the unique coastal lagoon in Algeria, and to increase knowledge on limpet species in South Mediterranean protected areas. Between the summer 2019 and the spring 2020, several biological and population dynamics aspects of the high-shore limpet Patella rustica were investigated. Based on length-frequency distribution analysis using the FiSAT II software, the age of sampled limpets ranged from one to five years old, and the estimated growth parameters were identified as L∞= 40.55 mm, K= 0.39 year-1, with a growth performance index (Φ') of 2.81. Morphometric analysis revealed significant positive allometric relationships indicating variations in body proportions during ontogenesis. Condition index exhibited strong seasonality, with the highest value (41.27±3.27) recorded during winter. Overall, this study revealed that P. rustica from El Mellah lagoon follows similar morphological and physiological patterns to other populations in the range of the species across oceanic and marine coastal waters. [ABSTRACT FROM AUTHOR]