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Breeding Ecology of the Iberian Chiffchaff Phylloscopus ibericus : First Data from North Africa

Bougaham Abdelazize Franck

Polish Journal of Ecology

2021

Vol. 69, nr 1

51--56

Till now, the breeding biology of several North African bird populations has been little studied, particularly that of the southern populations of Iberian chiffchaff Phylloscopus ibericus. In the present study, total of 31 nests of Iberian chiffchaff were monitored in the northeastern Algeria during 2013-2017. The nesting period, clutch and brood sizes, and reproductive success of the species were determined. The first egg-laying dates of the first broods were spread over the first twenty days of April. There were significant among-year variations in nesting seasons. The Iberian chiffchaff clutch sizes averaged 4.51 eggs. The number of hatchlings and fledglings averaged 4.09 and 3.54 nestlings, respectively. There is no correlation between the nest height above the ground and the hatching and the breeding success of the species. Predation and nest abandonment were the main causes of the breeding failure of the Iberian chiffchaff in studied population, however, in general the breeding success was high – 80.7%. Breeding data for the Iberian chiffchaff at the southern edge of its breeding range in North Africa show smaller clutches and production of fewer young compared to the common chiffchaff Phylloscopus collybita in Europe.

Grey Heron Ardea cinerea Productivity in Relation to Habitat Features and Different Spatial Scales

Manikowska-Ślepowrońska B., Ślepowroński K., Jakubas D.

Polish Journal of Ecology

2016

Vol. 64, nr 3

384--398

Life history traits of birds like survival or reproduction are strongly related to habitat features which affect food and nest-site availability. However, impact of habitat variables on life-history traits, which may be scale-dependent is barely studied. We investigated the relationships between landscape features and productivity (expressed as the number of 21–38 day old chicks per nest) of a colonial waterbird, the Grey Heron Ardea cinerea in northern Poland. In 2014 we analysed the landscape features (hydrographic features, habitat area, habitat patchiness and distances to the nearest water bodies, coastline, rivers/canals, buildings and roads) around the six colonies. We analysed all those features in four spatial scales around the colony: close proximity of the colony (0–1 km), closer foraging grounds (0–10 km), far foraging grounds (0–20 km) and far foraging grounds excluding close foraging areas and proximity of the colony (10–20 km). The differences in productivity among the colonies was not significant in the studied year (mean number of chicks ± SD: 3.57 ± 0.52). At each spatial scale excluding 10–20 km radius, Grey Heron productivity increased with increasing habitat heterogeneity and decreased with increasing length of rivers/canals and area of pastures. The results of this study indicate that the spatial scale of 0–10 km was the best to indicate relationships between landscape features and productivity in herons. Distance to the nearest river/canal banks, buildings and roads were related positively to productivity. Our study revealed the importance of landscape complexity of aquatic and terrestrial habitats for the Grey Heron productivity.