Trace metals in marine,brackish and freshwater prawns (Crustacea,Decapoda) from northeast Algeria

The concentrations of the trace metals Zn, Cu, Fe, Cd and Pb were measured in four caridean decapods; Atyaephyra desmaresti, Palaemonetes varians, Parapenaeus longirostris and Aristeus antennatus, from freshwater , estuarine and marine habitats in northeast Algeria variably affected by anthropogenic metal contamination. The two coastal species (P. longirostris and A. antennatus) are a food source for the local population. Accumulated metal concentrations varied interspecifically, and intraspecifically between sites and between seasons, except in the case of Aristeus antennatus. The fresh and brackish water species (Atyaephyra desmaresti and Palaemonetes varians) accumulated more Cd and Pb than their marine counterparts. Results are discussed with respect to anthropogenic inputs and the environmental conditions of the regions studied.     

Diet of breeding Eleonora's falcon Falco eleonorae in Algeria: Insights for the autumn trans‐Mediterranean avian migration

How environmental changes are affecting bird population dynamics is one of the most challenging conservation issues. Dietary studies of top avian predators could offer scope to monitor anthropogenic drivers of ecosystem changes. We investigated the diet of breeding Eleonora''s falcon in an area of Northeastern Algeria in the years 2010–2012. Feathers and insect remains originating from prey plucking behavior were analyzed, providing insights into the seasonally changing diet of this raptor, as well as the trans‐Mediterranean avian migration. A total of 77 species of birds (16 Sylviidae, 11 Turdidae, and 4 Emberizidae), 3 species of insects, and 1 lizard were identified among prey remains, reflecting a diverse diet. Diet composition and prey abundance varied seasonally, faithfully correlating with the passage of migrant birds as recorded from bird ring recoveries. Our findings suggest that dietary studies of predators might be deployed to investigate changes in bird migration. We discuss our results in the context of trans‐Mediterranean migration, with early‐season prey mainly comprising trans‐Saharan migrants (Apus apus and Merops apiaster) and late‐season prey being dominated by Mediterranean winter migrants (Erithacus rubecula, Turdus philomelos, Sylvia atricapilla, and Sturnus vulgaris). Notably, we observed a significant reduction in species richness of passerine remains in 2012, potentially highlighting a decline in the diversity of avian migrants.     

Sitting ducks: diet of wintering wildfowl in Lake Tonga,northeast Algeria

Dietary studies of five species of Anatidae (Gadwall Anas strepera, Shoveler Anas clypeata, Pochard Aythya ferina, Ferruginous Duck Aythya nyroca, and White-headed Duck Oxyura leucocephala) were carried out at Lake Tonga, northeast Algeria, from December 2011 to March 2012. Diet analysis of all five wintering species indicated a heavy reliance on seeds, which included a wide variety of aquatic plants, such as Myriophyllum spicatum, Ceratophyllum demersum, Sparganium erectum, Scirpus lacustris and Potamogeton pectinatus. Noteworthy is the paucity of ingested macroinvertebrates. Despite dietary overlap, the type, abundance and frequency of food consumed clearly indicated differences in resource use among the ducks. Incidentally, the study also highlighted the high vulnerability of threatened ducks to poaching (harvesting and disturbance) in a protected area. We discuss the implications of these findings for the management and conservation of wintering wildfowl and their North African habitats.     

Greater flamingo colonies around the Mediterranean form a single interbreeding population and share a common history

The greater flamingo Phoenicopterus roseus is a long‐lived colonial waterbird species, characterized by a large range encompassing three continents, a very limited number of breeding sites, and high dispersal abilities. We investigated both the phylogeographic history and the contemporary extent of genetic differentiation between eight different Mediterranean breeding colonies of greater flamingos sampled between 1995 and 2009, using both mitochondrial DNA and microsatellite markers. We found no significant differences in allelic richness or private allelic richness in relation to colony size. Overall, no genetic population differentiation was detected using either mitochondrial or microsatellite markers. F‐statistics and Bayesian clustering methods did not support any significant genetic structure. Analysis of both mitochondrial DNA and microsatellites indicated that populations have undergone a bottleneck followed by rapid growth and expansion. The average time since expansion was estimated to be 696 421 yr (90% CI: 526 316–1 131 579 yr). We discuss our results in relation to both the possible historical events accounting for the present genetic structure and relevance to conservation and management of the species.     

Effect of vertebrate and invertebrate kairomones on the life history of Daphnia magna Straus (Crustacea: Branchiopoda)

The history of selection of Daphnia magna populations living in North African temporary ponds may differ from populations inhabiting permanent ponds. Laboratory experiments were conducted to examine the effect of fish Gambusia holbrooki and invertebrate Notonecta glauca kairomones on the life history traits of the freshwater Cladocera Daphnia magna Straus. With fish kairomones, Daphnia reproduced early and had a significantly smaller size at first reproduction (SFR) and a smaller size of neonates compared to control. In contrast, daphnids reared in water treated with Notonecta glauca had no effect on the age at first reproduction but females were also smaller and produced smaller neonates.     

Rotifera, Cladocera, Copepoda, and Ostracoda from coastal wetlands in northeast Algeria

Two wetland complexes in the El Kala area, northeast Algeria, were sampled for zooplankton over a two-month period (mid-May to mid-July 1993). Some samples from 1976 and 1978 were also studied. A total of 98 taxa (51 species of Microcrustacea and 47 species of Rotifera) are recorded. Twenty-seven of these (26.5% overall) are new to Algeria and/or to the Maghreb and Africa. A significant fraction of Afrotropical species was found in all four groups, beside species of northern (European) origin, and at least one cyclopoid copepod with an Irano-Turanian range. These results confirm the El Kala wetlands as an important relict pocket of species of various historical and geographical origin, and highlight the urgency of safeguarding these sites. This revised version was published online in July 2006 with corrections to the Cover Date.     

Breeding ecology of the Little Bittern Ixobrychus minutus in northeast Algeria

Capsule This is the first study of the reproductive ecology of the Little Bittern Ixobrychus minutus in North Africa. During the study period, clutch size exhibited a sharp drop concurrent with a steady human encroachment and 30% habitat loss.

Aim To investigate the status, nest-site selection, breeding parameters, chick development and chick diet of Little Bittern in Algeria, under deteriorating habitat conditions

Methods Data were collected during surveys of all major Algerian wetlands (2002–08) and monitoring of breeding at Boussedra, a freshwater marsh in northeast Algeria, during the years 2005 and 2008.

Results Egg-laying spanned the period of 10 May to 30 June with one recorded case of a double brood in early July (n = 30). The mean clutch size in 2005 was 6.2?±?0.4 sd eggs per nest (n = 6 clutches), which was significantly higher than that of 2008, which amounted to 4.3?±?0.5 sd eggs per nest (n = 6 clutches), and this decline was associated with increased disturbance and loss of habitat. Overall, clutches suffered from a low rate of predation (17.6%) and displayed a high hatching rate (85.7%).

Conclusion Breeding parameters of the Little Bittern in North Africa are similar to elsewhere in Europe.     

From Europe to Africa and vice versa: evidence for multiple intercontinental dispersal in ribbed salamanders (Genus Pleurodeles)

Aim The intricate puzzle-like geography of the western Mediterranean is a product of long-term tectonic and orogenic events, supplemented by repeated climatic oscillations since the Pliocene. It offers numerous vicariance events that may be invoked to explain speciation in amphibians. We test for plausibility of two mutually exclusive Iberian–African vicariance hypotheses to explain the basal split within newts of the genus Pleurodeles: (1) the disconnection of the Betic arch c. 14 Ma and (2) the end of the Messinian salinity crisis 5.33 Ma. Location Specimens of P. waltl and P. poireti were sampled from 32 populations in Portugal, Spain, Morocco, Algeria and Tunisia. Methods Parts of three mitochondrial genes were sequenced (16S rRNA, cytochrome b, ATPase). Based on substitution rate constancy among lineages three different molecular clocks were calibrated to derive competing evolutionary scenarios for lineage evolution within Pleurodeles. Results One scenario was aligned with the dated fossil record and with historical events that are known to have enabled terrestrial faunal exchange between Europe and Africa. In Pleurodeles, such faunal exchange is more likely to have happened three times, resulting in the current pattern of species diversity and haplotype distribution: (1) following the disconnection of the Betic region from Iberia and connection of its southernmost part (present-day Rif Mountains) to Africa, c. 14 Ma; (2) closing of the Strait of Gibraltar prior to the Messinian salinity crisis, 5.59–5.33 Ma; (3) passive dispersal in recent times, caused by rafting on vegetation or inadvertent displacement by man. The results show that North African P. poireti populations comprise two distinct lineages; despite their geographical proximity, haplotype distribution within both lineages indicates totally different histories (range fragmentation vs. dispersal). Main conclusions Ribbed salamanders mainly evolved through allopatric speciation, driven by vicariance events. However, faunal exchange between Europe and Africa at the western end of the Mediterranean basin was linked to well-known events of physical contact between both continents. This sheds new light on the potential role of dispersal across marine barriers via rafting or even, presumably inadvertent, anthropogenic displacement for the initiation of speciation in amphibians.     

Distribution and breeding ecology of the Ferruginous Duck Aythya nyroca in Algeria

We conducted a survey of the distribution of Ferruginous Duck Aythya nyroca across Algeria and analysed the influence of nest-site characteristics on nesting success at a Ramsar site, Lake Tonga. The species was found to occupy different wetlands (freshwater lakes, brackish marshes and salt lakes) across three major climatic belts (subhumid coastal strip, semi-arid Hauts Plateaux and arid Sahara). Mean clutch size of successful nests was 13.3 ± 6.0 eggs (N = 26) with a hatching rate of 74% for successful clutches. Nesting success was recorded for 44% of nests with clutch desertion (72.7%) accounting for the majority of failed clutches. Egg size of the study population, which breeds at the southern limit of the species’ range, was significantly smaller than that of its northerly counterparts. Clutch size was negatively related to egg size and positively associated with depth of water below the nest, suggesting that older, more experienced or high-quality birds monopolised the safest sites. Successful clutches were significantly associated with tall vegetation, suggesting that when nesting is carried out mainly on offshore floating islets, protection against aerial predators and heat stress determine nesting outcome. Conspecific brood parasitism was significantly and positively associated with deferred egg-laying and smaller egg size, suggesting an age-dependent mechanism.