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Aquatic turtles are ectotherm animals whose activities are conditioned by their environment. The objective of this study is to asses the heatwave effects on the abundance of aquatic turtles. The resulting study was conducted from spring to fall 2022, in a water plan next to Guerbes Sanhadja wetlands eco complex, known for the density of aquatic turtles it hosts. Temperature and rainfall data, as well as satellite images and field photography, were utilised to monitor the drying of the water plain. . Freshwater turtles were counted remotely every one hour from a specific location. The results obtained confirm the resumption of aquatic turtle activity, particularly marked in summer, but the persistence of heatwave, with abnormally high air temperatures and very low rainfall, caused the gradual drying up of the water plan and a sharp drop in turtle’s numbers.

Habitat preferences were studied in sympatric populations of two Lacertids, Psammodromus algirus and Acanthodactylus erythrurus (Lacertidae) from the National Park of El Kala (north-eastern Algeria). The relationship between habitat physical structure and population densities was studied in order to establish eventual segregation between the two lizards. A difference exists between the two species in their distributions. Acanthodactylus erythrurus is a strictly terrestrial species, usually found on sandy and more open grounds than Psammodromus algirus which can penetrate dense vegetation and look for sunny locations by climbing on shrubs; a behavior which A. erythrurus does not control. Our results confirm spatial segregation on a microhabitat scale, supporting the conclusions that microhabitat selection is an important factor in lizards community organization and contributing to reduce potential competition.

Spur-thighed tortoise is a vulnerable species, the local declines of populations require an imperative need for conservation. Research on habitat use is essential for understanding population ecology. To investigate the home range and movement patterns we studied a population which occupies an enclosed area of 30 ha in northeastern Algeria. Studies of movement showed that home ranges were substantially smaller than in Spain. This difference was due to the high trophic availability with significant richness in plants which make part of the diet of the tortoise. The home range varied from 0.287 ha in males to 0.354 ha for females; there was no sexual difference. The males are the most active with a distance of 3.79 m/d. Females and juveniles are respectively about 2.25 m/d and 2.11 m/d. The distance moved each day do not vary significantly by sex and ages. Results from this study are important for establishing conservation strategies for this vulnerable species.

We investigate the dynamics of solidification of a charged colloidal dispersion using an original microfluidic technique referred to as micropervaporation. This technique exploits pervaporation within a microfluidic channel to extract the solvent of a dilute colloidal dispersion. Pervaporation concentrates the colloids in a controlled way up to the tip of the channel until a wet solid made of closely packed colloids grows and invades the microfluidic channel. For the charged dispersion under study, we however evidence a liquid to solid transition (LST) preceding the formation of the solid, owing to the presence of long-range electrostatic interactions. This LST is associated with the nucleation and growth of domains confined in the channel. These domains are then compacted anisotropically up to forming a wet solid of closely packed colloids. This solid then invades the whole channel as in directional drying with a growth rate which depends on the microfluidic geometry. In the final steps of the solidification, we observed the occurrence of cracks and shear bands, the delamination of the wet solid from the channel walls, and its invasion by a receding air front. Interestingly, this air front follows specific patterns within the solid which reveal different microscopic colloidal organizations.

In most situations, drying is accompanied by the development of strong concentration gradients. Here, we evidence theoretically and experimentally that there exist microfluidic geometries for which confined drying becomes homogeneous, i.e., with no concentration gradient regardless of the type of solute involved in the process; ions, molecules, and colloids do concentrate in the same way providing a limited set of assumptions concerning the microfluidic geometry. It thus makes possible the establishment of phase diagrams of multi-component mixtures at the nanoliter scale.

Bird nests are often heavily infested with several haematophagous ectoparasite species that drain energy and other essential resources needed for the development of the rapidly growing chicks. The nutritional requirements of altricial chicks can only be satisfied by the parents frequently bringing prey to the nest. In a 3-year study, we tested experimentally whether a parasite-induced change in the nutritional budgets of the chicks in an Algerian population of the Blue Tit, could be compensated by a response in parental food provisioning behaviour. We found that nestling body mass and size did not differ between heat-treated ‘parasitefree’ nests and heavily infested control nests. However, after controlling for potential confounding variables (laydate, clutch size, chick age, year), we found that broods of heavily infested control nests were more frequently visited and fed than broods that received antiparasite treatment. The results are discussed in the framework of theory related to behavioural responses of hosts to parasites.

A total of 100 specimens of Emys orbicularis were collected and marked at Lake Tonga (northeastern of Algeria) during 3 consecutive years (2013, 2014, 2015). Most of the turtles inhabit a canal where they remain throughout the whole activity season (March to October) and where they overwinter as well. Carapace Length (CL) and body weight (BW) were measured for each individual of E. orbicularis . The size of the turtles of our population was more similar to those of northern European populations than to the Mediterranean populations; females were significantly larger than the Spanish and Italian populations. The population size was calculated as 108.50 and the density as 8.63 turtles/ha. From 6.52 to 12.77% of the population were juveniles. The adult sex ratio was slightly in favor of males (males:females = 1.12, P < 0.005).

International audience; Structure and interactions stabilising the lamellar stack of mixed lipid bilayers in their fluid state are investigated by means of small-angle X-ray scattering. The (electrically neutral) bilayers are composed of a mixtures of lecithin, a zwitterionic phospholipid, and Simulsol, a non-ionic cosurfactantwith an ethoxylated polar head. The soft confinement of the bilayer hydrophilic components is varied by changing hydration and bilayer composition, as well as the length of the cosurfactant polar head. Structural transitions are observed at low hydration, in the stacking order for the longer cosurfactant,and in the mixed bilayers for the shorter one. At higher hydration, the swelling of the lamellar stacks occurs with a significant, but continuous evolution in the mixed bilayer structure. The bilayer structural changes are discussed in analogy with the so-called “brush-to-mushroom” transition induced by lateralconfinement, relevant for long linear polymers grafted onto rigid surfaces, taking also into account the role of vertical confinement.

Received July 5, 2013; Accepted November 6, 2013; Published December 31, 2013, Background: Climate change potentially has important effects on distribution, abundance, transmission and virulence of parasites in wild populations of animals. Methodology/Principal Finding: Here we analyzed paired information on 89 parasite populations for 24 species of bird hosts some years ago and again in 2010 with an average interval of 10 years. The parasite taxa included protozoa, feather parasites, diptera, ticks, mites and fleas. We investigated whether change in abundance and prevalence of parasites was related to change in body condition, reproduction and population size of hosts. We conducted analyses based on the entire dataset, but also on a restricted dataset with intervals between study years being 5–15 years. Parasite abundance increased over time when restricting the analyses to datasets with an interval of 5–15 years, with no significant effect of changes in temperature at the time of breeding among study sites. Changes in host body condition and clutch size were related to change in temperature between first and second study year. In addition, changes in clutch size, brood size and body condition of hosts were correlated with change in abundance of parasites. Finally, changes in population size of hosts were not significantly related to changes in abundance of parasites or their prevalence. Conclusions/Significance: Climate change is associated with a general increase in parasite abundance. Variation in laying date depended on locality and was associated with latitude while body condition of hosts was associated with a change in temperature. Because clutch size, brood size and body condition were associated with change in parasitism, these results suggest that parasites, perhaps mediated through the indirect effects of temperature, may affect fecundity and condition of their hosts. The conclusions were particularly in accordance with predictions when the restricted dataset with intervals of 5–15 years was used, suggesting that short intervals may bias findings., JMP was supported by a JAE grant from Consejo Superior de Investigaciones Científicas. SM-JM, FdL-AM, JF, JJS and FV were respectively supported by projects CGL2009-09439, CGL2012-36665, CGL2009-11445, CGL2010-19233-C03-01 and CGL2008-00562 by the Spanish Ministry of Science and Innovation and FEDER and project EVITAR by the Spanish Ministry of Health. FV was also supported by the European Regional Development Fund. MACT was funded by a predoctoral FPU grant from the Spanish Ministry of Education (AP20043713).

The widespread use of artificial nestboxes has led to significant advances in our knowledge of the ecology, behaviour and physiology of cavity nesting birds, especially small passerines. Nestboxes have made it easier to perform routine monitoring and experimental manipulation of eggs or nestlings, and also repeatedly to capture, identify and manipulate the parents. However, when comparing results across study sites the use of nestboxes may also introduce a potentially significant confounding variable in the form of differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained. However, the use of nestboxes may also introduce an unconsidered and potentially significant confounding variable due to differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained. Here we review to what extent the characteristics of artificial nestboxes (e.g. size, shape, construction material, colour) are documented in the 'methods' sections of publications involving hole-nesting passerine birds using natural or excavated cavities or artificial nestboxes for reproduction and roosting. Despite explicit previous recommendations that authors describe in detail the characteristics of the nestboxes used, we found that the description of nestbox characteristics in most recent publications remains poor and insufficient. We therefore list the types of descriptive data that should be included in the methods sections of relevant manuscripts and justify this by discussing how variation in nestbox characteristics can affect or confound conclusions from nestbox studies. We also propose several recommendations to improve the reliability and usefulness of research based on long-term studies of any secondary hole-nesting species using artificial nestboxes for breeding or roosting.

Like many other seasonally breeding birds, Blue Tits raise their chicks mainly at the time when numerous caterpillars attack fresh oak leaves. This paper reports on the results of the first quantitative study of food ecology in combination with the breeding biology of a North African population of Blue Tits occupying distinct patches of oak habitat (high-altitude semi-evergreen zeen oak versus low-altitude evergreen cork oak). To check for between-habitat differences in intensities of nest parasites feeding on chicks, all nests monitored were heat-treated during the chickraising stage. The peak demands of the chicks were found to coincide with the peak date of caterpillar availability in both habitat types. Food availability was much higher in the semi-evergreen habitat, and the diversity of prey delivered to the chicks was higher in the evergreen habitat. Surprisingly, breeding success was very low in both habitat types. It is suggested that several environmental constraints may cause maladapte...

The distribution of the Whiskered Tern (Chlidonias hybridus) is scattered, numbers fluctuate and they are threatened in many regions. Its breeding ecology has only occasionally been studied so far. It is relatively common in some North African wetlands. This study was carried out on Lake Tonga, northern Algeria, south of El-Kala (3651’N; 0820’E) in 1996 and 1997, with 169 and 215 initiated clutches studied, respectively. Basic characteristics of the Whiskered Tern breeding ecology studied were: laying date, clutch size, hatchling number, nest size and shape and egg size. Hatching success differed significantly between 1996 and 1997, probably due to weather. Laying date did not influence breeding parameters. Clutch size and hatching success were correlated with size and shape of nests. Hatchability was also correlated with egg length (negatively) and mass (positively). Relationships between breeding characteristic in relation to weather are discussed.