During the 20th century, Mediterranean landscapes underwent extensive changes. In particular, decreasing grazing pressure combined with abandonment of agricultural uplands favoured the development of Mediterranean forests with a corresponding reduction of open habitats and landscape diversity. In some parts of the Mediterranean basin, including our study area, the reduction of open landscapes took place at the same time as a rapid decline in rabbits as a result of myxomatosis. This study assesses the impact of past changes in landscape and rabbit density on the density and the breeding performance of the eagle owl Bubo bubo, one of the largest predators of Mediterranean ecosystems. Eagle owl density, nest site structure and composition at the landscape level, diet and fecundity of 35 eagle owl nesting territories was analysed for 27 years. The study area is characterized by two distinct areas, the border of the massif and the interior, in which past changes acted differently. Eagle owls in the interior were simultaneously affected by the loss of rabbits, a shift to smaller prey, and by open areas reverting to forest. All of these factors reduced the foraging ef®ciency of the owls. When myxomatosis decimated the rabbit population, owls in the border area switched to other mammals, birds and ®sh, whereas in the interior, alternative prey were less abundant. The main impacts of reduced prey availability and landscape diversity on interior pairs were: (1) lower density of breeding pairs; (2) lower diversity in landscape structure and closer habitats; (3) lower richness and diversity in the diet; (4) later egg-laying dates; (5) lower productivity.

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By means of satellite telemetry, the migrations of three young Egyptian vultures (Neophron percnopterus) from France and Bulgaria were studied and data obtained (over 4,300 Argos locations) to describe movement patterns, timing of migration, routes followed, speed of flight and ranging behaviour in Africa.

If individuals of the same population inhabit territories different in landscape structure and composition, experiencing habitat-specific demographic rates, then the landscape features become major determinants of the overall population characteristics. Few studies have tested how habitat-specific demography interacts with landscape heterogeneity to affect populations of territorial species. Here we report a 29-year study of an eagle owl (Bubo bubo) population in southern France. The aim of this study was to analyse how habitat heterogeneity could affect density and breeding performance. Mean productivity for the overall sample was 1.69±0.76 fledglings per breeding pair and, after controlling for year effect, significant differences between territories were detected for productivity. A positive correlation was found between the percentage of pairs producing 50% of the annual fledged young (an index of the distribution of fecundity among nesting territories) and the mean reproductive outputs, that is the heterogeneous structure of the population determined that most/all pairs contributed to the annual production of young during good years, but the opposite during poor years (i.e. fewer pairs produced the majority of fledglings). Mean reproductive output was positively affected by percentage of open country and diet richness. Although other factors different to territory quality could affect demography parameters (e.g. quality of breeders), our results clearly showed a significant correlation between landscape features and population productivity.

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