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We investigated the odonates of Wadi Cherf, a tributary of Wadi Seybouse, and explored the main environmental factors that may be important drivers of the abundance and diversity of Odonata assemblages. PCA analyses demonstrated a significant altitudinal gradient associated with water flow, temperature, vegetation cover, substrate and adjacent land use. Notably, pollution was a dominant structuring factor and the most widespread species, Ischnura graellsiiand the North African endemic Platycnemis subdilatata, were the most pollution-tolerant species. Similarly, co-inertia analysis indicated that environmental factors could account for 70% of the co-variation in shaping odonate assemblages. Equally important, threatened species were associated with less degraded but vulnerable habitats, most susceptible to anthropogenic impacts. There is thus a need to develop monitoring tools to assess the ecological integrity of North African rivers and implement a management plan that considers both connectivity and heterogeneity to ensure that Wadi Cherf, a sanctuary to three threatened species Calopteryx exul(EN), Coenagrion mercuriale(EN) and Gomphus lucasii(VU), continues to provide critical ecosystem functions.

SummaryA survey of the hoverflies (Diptera: Syrphidae) of the region of Guelma, northeast Algeria, was carried out from August 2011 to  July 2013. A total of 31 species was recorded with six (Scaeva mecogramma, Epistrophe melanostoma, Syrphus vitripennis, Brachypalpus valgus, Merodon calcaratusand M. chalybeus) new to Algeria. Of these, three species (E. melanostoma, M. calcaratus andM. chalybeus) are also new additions to the entomofauna of North Africa. The results complement those of a previous study covering Numidia and Tebessa and provide a more comprehensive view of the phenology and distribution of Syrphidae across northeast Algeria. An improved knowledge of the distribution of North African hoverflies will contribute to a better assessment of the status of each taxon and inform conservation efforts.

AbstractEcological and evolutionary processes can conveniently be explored through the simplified communities of temporary ponds. In order to investigate the potent roles of predation in structuring zooplankton communities, we used a manipulative study to analyze the impact of eastern mosquitofish, Gambusia holbrooki, on a set of 24 temporary ponds. Fish were introduced at different densities (0, 8, 16 and 80 mosquitofish), and zooplankton assemblages were monitored monthly between January and May. Fish predation decreased markedly the overall abundance of zooplankton. Large crustaceans (Anostraca and Calanoida) were rapidly eliminated, while Cyclopoida and Cladocera peaked in March before in turn disappearing in the later stages of the hydroperiod. These results are congruent with the theory supporting the influence of both predation and competition as major interacting forces shaping freshwater communities.

The status of waterbirds breeding in protected areas in North Africa needs constant monitoring because of a naturally fluctuating environment and permissive attitudes towards illegal activities likely to negatively affect population dynamics of threatened species. We present the results of a study conducted at a protected site, Lake Tonga, north-eastern Algeria, on a breeding population of Ferruginous Duck Aythya nyroca, a Near-Threatened duck subjected to considerable pressure from egg-pilfering and illegal hunting. Two distinct habitats within the lake were used by Ferruginous Duck: an Alder carr (Alnus glutinosa) and floating islets across the lake. The mean clutch size was 9.51±1.84 eggs (N= 51 clutches) with hatching rate of 80.7% for successful clutches. Breeding success was low (37%) with predation (33%) and clutch desertion (17%) accounting for the majority of failed nests. The probabilities of nest failure and nest desertion increased with a delayed onset of egg laying. Predation was not significantly associated with egg laying date and vegetation cover, but late breeders nesting in dense vegetation seemed to suffer less predation. Conspecific brood parasitism was positively associated with nest size, whereas interspecific brood parasitism was marginally associated with water depth. We discuss different hypotheses concerning nest desertion, and argue that illegal hunting and disturbance may best explain why birds desert their nests.

A survey of the Gomphidae of Algeria and the Maghreb was carried out during the period 2013–2014. Sampling of eight main wadis across northern Algeria was undertaken and adults and exuviae were recorded. The survey yielded six species of Gomphidae. Among these, we report on the rediscovery of the Critically Endangered Lindenia tetraphyllain Algeria, recorded in the nineteenth century and deemed to have been extinct after an absence of more than a century and a half. An exuvia was collected at Wadi Saoura, which constitutes the first proof of the breeding of this species in Algeria and the third record for North Africa. We also recorded a pale form of Onychogomphus uncatus, morphologically distinct from typical Moroccan and European phenotypes, suggesting some degree of subspeciation and inviting further taxonomical investigations of the genus Onychogomphusin North Africa. Due to increasing water demand, Gomphidae and their habitats are under great pressure in the Maghreb. Specific threats and conservation measures are discussed.

The aim of this study was to identify the ectoparasite community that may be found on the body of Glossy Ibis chicks Plegadis falcinellusin two Algerian wetlands, Chatt and Lake Fetzara, during the breeding season of 2010. Birds were parasitized by the following chewing lice (Phthiraptera: Amblycera, Ischnocera) species at both study sites: Plegadiphilus plegadisand Colpocephalum leptopygos(both Menoponidae), Ardeicola rhaphidiusand Ibidoecus bisignatus(both Philopteridae). In addition, one tick (larva) Ixodes ricinuswas also found at Lake Fetzara. All these ectoparasites were recorded in Algeria for the first time. Results showed that chewing lice varied in their spatial distribution at the infracommunity level with some species displaying no microhabitat preferences, whereas others confined themselves to specific body parts of their hosts. The recorded frequency pattern of chewing lice followed the negative binomial distribution.

Between 2010 and 2012, we studied the breeding ecology of the common moorhen Gallinula chloropusat Lake Tonga, north-east Algeria. Nests were low lying (mean ± SD = 13.64 ± 5.07 cm) and located in tall, dense stands of Scirpus lacustris(72%). The egg-laying period was relatively short, between mid-April and the end of June, peaking in the first half of May. The mean overall clutch size ± SD was 7.03 ± 2.52 (N = 58 clutches) with a slight seasonal downward trend. Rates of successful clutches increased with egg-laying date and water depth mainly due to the seasonal decrease in nest predation and nest flooding. Nest predation, in contrast to nest flooding, was also negatively associated with water depth. The study documented relatively frequent cases of conspecific brood parasitism as well as rarely reported events of interspecific brood parasitism involving the common moorhen both as a host and as a parasite of other avian species.

During the period 2002–2012, we assessed the breeding status of the Grey Heron Ardea cinereain Algeria by surveying all the major wetlands in the region. We located two distinct breeding sites; one of them was recorded for the first time. We also investigated nest site selection, measured breeding parameters and derived a growth curve for developing chicks. Although wintering Grey Herons increased in numbers in the region, the number of breeding pairs did not change markedly over the past century. The reasons for the scarcity of Grey Heron breeding pairs in Algeria and in the rest of North Africa are discussed.

The ecological diversity and distribution of ectoparasites on Greater Flamingo chicks (Phoenicopterus roseus) were investigated in Algeria at two distinct sites: Ezzemoul (Hauts Plateaux) and Safioune (Sahara) at the end of the breeding seasons of 2009 and 2011. Results from the first records for the Greater Flamingo in North Africa, indicate that they were infested by the following louse species: Colpocephalum heterosomaPiaget and Triniton femoratumPiaget (Menoponidae); Anaticola phoenicopteri(Coinde) and Anatoecus pygaspisNitzsch (Philopteridae). These data support the hypothesis of a connectivity of the Greater Flamingo metapopulation across the Mediterranean region. The results also suggest that there was a spatial segregation in the distribution of the various louse species across distinct body parts of their hosts. Adaptive explanations for this niche partitioning are suggested.

AbstractWhen comparing the phenology of species within the family Lestidae in Numidia, northeastern Algeria, we found that: (1) four of five species—Lestes barbarus, L. numidicus, L. viridis, and Sympecma fusca—feature a prolonged pre-reproductive period approaching five (Lestesspp.) or eight months (S. fusca); (2) adults of L. numidicus, and probably of S. fusca, move to upland refuge sites in summer, whereas those of L. barbarusand L. viridisaestivate in alder carrs in lowlands close to reproductive sites; and (3) adults of all five species exhibit distinct spatial and/or temporal segregation.

AbstractForty-five species of Odonata have been recorded within Numidia, which includes the El Kala and the Guerbes-Senhadja wetlands in northeastern Algeria. Five species are new to the area. Changes occurring in dragonfly diversity over a century and a half are discussed. This paper (Part I) deals with the status and spatial distribution of each recorded taxon.

AbstractThis paper, a companion to Part I which treated status and distribution of Numidian Odonata, summarizes current knowledge of their seasonal ecology and identifies areas where promising research avenues exist. Annual patterns of adult occurrence and reproductive activity are used to infer life cycles, with particular reference to strategies that enable species to bridge the hot, dry summer, and to propose a phenological classification applicable to south-temperate north-African Odonata.

AbstractA survey of the dragonflies of Algeria, spanning nine years, has yielded 53 species. Past records of another 10 species are believed to be genuine, making up a total of 63 species for the country. We try to clarify the status of these supplementary species and also provide information on the current distribution and present status of all recorded species.