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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.

The breeding distribution of the Gull-billed Tern Gelochelidon nilotica in Algeria is poorly known as the species is mainly associated with highly unstable habitats. We conducted a survey of the distribution of the species across all major Algerian wetlands and monitored a breeding colony at El Goléa during 2009. The species is usually described as a passage migrant in the Sahara, but its status may have to be reconsidered following our discovery of a small colony nesting on an islet in Sebkhet El Maleh, El Goléa. The colony consisted of 25 birds which built nine nests and foraged exclusively in and around the salt lake. Laying of eggs began in mid-April, in synchrony with high temperatures and strong evaporation. Clutches varied between 1 and 3 eggs but none was successful. The gradual drop in water level and subsequent drying of the Sebkha coincided with the first hatchings, exposing the first hatchlings to mammalian predation arising from the intrusion of jackals Canis aureus, which entirely destroyed the colony.

Ecological 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.

Between 2010 and 2012, we studied the breeding ecology of the common moorhen Gallinula chloropus at 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 cinerea in 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.