In oviparous taxa such as birds, clutch characteristics (e.g. egg size, egg mass and the number of eggs) can be considered as energetic investment in reproduction. In this paper, we study variation in the principal component indices of egg size and shape in Rufous Bush Chats (Cercotrichas galactotes) breeding in date palm plantations in the Al Amri Oasis, north Algeria, in 2008–2009 and 2011–2013. For descriptive and comparative purposes, we also present characteristics of egg length, breadth, volume, shape and mass. The size and shape indices as well as dimensions and masses of the eggs laid by particular females tended to be similar to one another, with most variation occurring between clutches (significant repeatabilities for all egg traits). Variation in the size of eggs was influenced by the year-laying date interaction, while variation in the shape (elongation) of eggs was marginally significantly affected by the year-laying date interaction. Year had a significant factor effect on the size of eggs. We also found that hatching success was affected by interactions between year and egg size and shape principal components, thus confirming the existence of fitness-related consequences of variation in the traits of Rufous Bush Chat eggs. Notably, we found that in some years hatching success increased with the elongation of eggs.

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Spinosad is a biopesticide, derived from fermentation by the soil-dwelling actinomycete, Saccharopolyspora spinosa, which is used to control a variety of insects. Spinosad kills a wide range of insect pests when ingested or topically applied, by overexciting the nervous system, yet is harmless to mammals and many predatory insects. Other modes of action of this insecticide have not been documented. Here, we report that a non-lethal dose of spinosad causes adult male and female German cockroach, Blattella germanica, to exhibit altered responses to their aggregation pheromone as well as to have a changed cuticular hydrocarbon profile.

The placement and size of birds’ nests may have direct consequences for their breeding success. Here, we examined if the location and design of Rufous Bush Chat ( Cercotrichas galactotes) nests influenced their breeding success in the Al Amri Oasis, at the base of Saharan Atlas, north Algeria, in 2008–2009 and 2011–2013. The mean height of nests above ground level was 2.26 ± 0.09 (SE) m, ranging from 0.5 to 4.9 m and the mean nest-cup volume was 246.60 ± 11.82 (SE) cm3, ranging from 102.95 to 471.24 cm3. Nest-cup volumes were positively associated with the height of nests and breeding success was strongly positively associated with the height of nests above ground level. We conclude that pairs of Rufous Bush Chats that bred in higher nests had higher levels of breeding success because they suffered lower predation rates from ground-based predators than lower nests. Lower nests, which are more vulnerable to ground-based predators are likely to be smaller in order to make them less visible to visually searching predators and may also fit more snugly into the smaller leaf stems of smaller palms. These findings agree with the hypothetical predictions based on the properties of palm physical structure as a support for nests, the tree size structure of plantations and the risk of predation.

An updated checklist of the mosquitoes (Diptera: Culicidae) of Algeria based on records published from 1903 to 2021 is presented. Fifty-three species belonging to seven genera are known with reasonable confidence to occur in the country, including Aedes (15 species), Anopheles (15), Coquillettidia (2), Culex (14), Culiseta (5), Orthopodomyia (1) and Uranotaenia (1). Two additional species, Culex simpsoni Theobald, 1905 and Uranotaenia balfouri Theobald, 1904, are provisionally regarded as present in Algeria. Published records are listed for each species, with indication of synonymous usage and variant spelling of names where applicable. The type locality of Aedes biskraensis Brunhes, 1999 is restricted to Seriana in Sidi Okba District in Biskra Province. Problematic species and doubtful occurrence records based on apparently misidentified specimens and confused taxonomy are discussed. Notes on taxonomy and medical importance are provided for the more important species.