Characterization and diversity of macroinvertebrates of the Bouhamdane Stream (northeast of Algeria)

Freshwaters are among the most threatened ecosystems, particularly in North Africa where urbanization and climate change are exerting an important pressure on aquatic fauna. Long-term investigation of macroinvertebrates is one of the best ways of tracking and understanding the influence of environmental and anthropogenic pressures on community dynamics. In this study, we focus on determining the community structure and diversity of benthic macroinvertebrates as well as the state of aquatic physicochemical parameters in the Bouhamdane Stream, near the outlet of Bouhamdane dam, Seybouse watershed, north-eastern Algeria. We carried out a bi-monthly sampling of macroinvertebrates and nine water physicochemical parameters from September 2017 to July 2018 at three sites. Results show that the collected macroinvertebrates (6756 individuals) belong to 15 families and 12 orders. The abundance of the macrofauna consisted of 88.19% crustaceans, 7.74% insects, 3.7% molluscs and 0.16% annelids. Physicochemical analyzes (depth, turbidity, pH, dissolved O2, temperature, salinity, and conductivity) showed variability among sites. The families of Gammaridae and Baetidae were the most frequent and the most abundant on all the stations. The results indicate that aquatic macroinvertebrates constitute good indicators of the biological quality of water. This study shows that even with the occurrence of regular dam water discharge, the macroinvertebrate community is still able to persist either through adaptation to high water velocity or high colonization rate.

First data on cetacean strandings and in situ observations along the Algerian coast

Data on cetaceans within the pelagic ecosystem remains scarce in the Algerian basin. This is linked to a lack of investigations stemming from the difficulty of quantitative population evaluation through oceanographic surveys and/or strandings statistics. In this context, we considered that it is appropriate to focus on data acquisition from offshore observations as well as setting up a network for monitoring strandings on sites scattered along the Algerian coast. During 10 oceanographic surveys conducted in two Algerian coasts sectors (eastern and central) we observed a total of 245 delphinids corresponding to 8 species that had an irregular distribution. We also identified 83 individuals belonging to five species that stranded between 2007 and 2017.

A fine-grained analysis of a Monk parakeet (Myiopsitta monachus) nest suggests a nonhomogeneous internal structure

We report first data on the fine-grained structure (branch diameter, length and diversity) in three different sectors [core (central side), buffer (peripheral side), and nest chamber)] of a nest of Monk Parakeets (Myiopsitta monachus) from a non-native breeding site located in an urban park (Rome, central Italy). The central core sector was characterized by longer and thicker branches capable of supporting the nest. The peripheral part (buffer) was characterized by less long and less thick branches with the function of completing the structure. Branches building the nest chamber were shorter and less thick but very diversified in size, because they included both small branches supplied inside the chamber and longer branches covering it. This diversification of the internal chamber (nest chamber) could be functional to maintain stable temperatures of incubator chambers compared to large fluctuations outside the nest. The presence of leaves of herbaceous species (Hordeum leporinum) could play a bactericidal role for the nest plant material.

The effect of climate change on habitat suitability and a distribution model of the Iranian fat-tailed gecko, Eublepharis angramainyu Anderson and Leviton, 1966 (Sauria: Eublepharidae) since the Last Interglacial to 2050

Surveying the role of climate changes on the species distributions in the past, present and future, and correlating these with changes in distribution ranges have attracted considerable research interest. The leopard geckos of the genus Eublepharis Gray, 1827 (family Eublepharidae), as a vicariate group, comprises six valid species distributed from Turkey through the Iranian Plateau to India, of which E. angramainyu, E. macularius and E. turcmenicus occur in Iran. In this study, we modelled the potential distribution areas for E. angramainyu and determined the suitable habitats in the past (the last interglacial [LIG] and mid-Holocene [MH]), present (1950–2000), and also predicted four scenarios in the future (2050) by using the maximum entropy approach (MaxEnt). The obtained models indicated very good values of the area under curve (AUC): LIG = 0.996 ± 0.003, MH = 0.996 ± 0.004, contemporary period = 0.995 ± 0.004, and the future = 0.997 ± 0.002. Precipitation of the coldest quarter and precipitation of the warmest quarter were the most important factors shaping the distribution of E. angramainyu. As it seems, climatic changes have been responsible for a southward shift in distribution and suitable habitats of E. angramainyu from the LIG (~150,000–120,000 years ago) to the future. The representative concentration pathway (RCP) 2.6 scenario model of the future predicted a much more restricted distribution and less suitable habitats due to radiation of the forcing level which reaches a value of around 3.1 W/m² by mid-century and returns to 2.6 W/m² by 2100.

Variation in life history traits of the Sahara frog (Pelophylax saharicus) with elevation and predation in northeast Algeria

Ectotherms respond quickly to environmental change and thus are prone to show adaptive mechanisms across a gradient of environmental conditions. Frogs in particular have been widely used in experimental ecology to test life history theory and plasticity across gradients. However, little has been carried out on the North African Sahara frog (Pelophylax saharicus) which experiences a particularly stressful environment characterized by warm and dry conditions. In this study, we documented the adaptation of P. saharicus life history across elevation in northeast Algeria using six different populations spanning across a range of 5–1000 m. Based on snout-vent length (SVL) and body weight, we estimated the growth rate of tadpoles of each population in two predation treatments (presence and absence of Anax sp. dragonfly chemical cue). We found that the fastest-growing population was that at low elevation, followed by intermediate elevations and high elevation. Predation affected only low-elevation populations, increasing the rate of growth in body weight but not in SVL. Our results indicate that P. saharicus has adapted its life history to different conditions across elevation, suggesting low gene flow between low- and high-elevation populations.

Age and growth of large scale scraper (Capoeta aculeata) in the Gizehrud River, Tigris basin

The large scale barb, Capoeta aculeata is a little known species native to Iran. Its age and growth were studied in 377 specimens collected monthly from the Gizehrud River in Lorestan Province (Tigris basin) during May 2014–May 2015. Sex ratio was 1M:2.1F. The maximum age of both female and male specimens was 6+ years. The most common age group of both male and female fish was 4+. The fork length ranged from 12.2 to 20.8 cm (17.4 ± 1.2SD) and weight from 32 to 188 g (93.6 ± 21.8SD). The estimated length-weight relationship of male specimens was W = 0.0161FL3.012, (r2 = 0.82) and that of female specimens W = 0.0248FL2.87, (r2 = 0.79). This relationship showed that growth of both Capoeta aculeata sexes was isometric. The estimated von Bertalanffy growth model for males was Lt= 20.9[1-e-0.57(t+0.2)] and for females Lt = 20.3[1-e-0.56(t-0.8)]. The growth performance index was estimated at 5.4 and 5.5 for males and females, respectively, indicating a similar growth rate for both sexes.

Polychaetes as bioindicators of environmental pollution: Impact of bisphenol A on the reproduction rate of Ophryotrocha diadema (Åkesson, 1976) (Eunicida: Dorvilleidae)

Bisphenol A (BPA) is one of the most used additives in the production of many plastic products and may be released into the environment by commonly used products, such as food containers and polycarbonate bottles. BPA is recognized as an endocrine disruptor able to produce adverse effects on the reproduction system of benthonic and pelagic species. Polychaetes of the genus Ophryotrocha are small worms living amongst the interstitial fauna in nutrient-rich and polluted habitats. Owing to easy rearing in the laboratory and short generation times, this species is a useful model organism for studying different biological aspects. This study describes the effects of different BPA concentrations on egg production in Ophryotrocha diadema. We tested six different concentrations of BPA in a 5-week experiment. Strong negative correlation between BPA concentrations and the number of eggs produced was found. The t-test revealed a significant reduction in egg production after exposure to BPA concentrations over 1461.1 μg/L. The latter concentration value is higher than that observed in the marine environment, although for many species of crustaceans, echinoderms and isopods, the impairment of reproductive function was observed even at much lower BPA concentrations.

First record of Mothocya arrosor Bruce, 1986 parasitizing Euleptorhamphus viridis (van Hasselt, 1823) from India

The first record of Mothocya arrosor Bruce, 1986 parasitizing ribbon halfbeak fish Euleptorhamphus viridis is here reported from the southeast coast of India. The important characters distinguishing M. arrosor from other species in the genus include the body slightly twisted to one side, dorsum weakly convex, coxae of pereonites 6 and 7 distinctly rounded, pleon more completely overlapped by pereonite 7, pleonite 1 scarcely visible in dorsal view, uropod peduncle longer than rami, lacking strongly convex medial and lateral margins. The damage of gill rakers and erosion of gill lamellae were the acute gross lesions observed as a result of isopod infestation.

The synanthropic Common Moorhen (Gallinula chloropus) in North Africa: The Impact of habitat degradation on breeding performances

We carried out a study on dynamics of the Common Moorhen, Gallinula chloropus, a synanthropic rallid (Aves, Gruiformes), to elucidate the adverse effects this species has possibly suffered from the markedly increased habitat degradation that has been taking place over the last decades at Boussedra Pond, north-eastern Algeria. During the period 2015–2018, this wetland-related species showed an annual 35.4% decrease in its numbers, and the number of breeding pairs, which was monitored between 2008 and 2018, experienced an annual drop of 4.9%. The clutch size, a key determinant of breeding performance, averaged 4.7 ± 1.0 eggs (N = 26 clutches) in 2018 and was significantly lower than those reported in previous studies. As a result of anthropogenic activities, the size of the marsh decreased by more than 50% over the 1984–2018 period. The long-lasting shrinkage of this relict wetland was accompanied by the expansion of built-up areas (>50%) and cultivated plots, and, also, by a marked reduction in natural both wet- and dry-land habitats in its vicinity. We suggest that the decrease in the population trend and the breeding performance of the Common Moorhen could be indicative of the species stress response to the long-lasting land conversion, pressuring the relict habitat of Boussedra Pond.