WIWO-reports published

With the establishement of long-term breeding bird monitoring schemes in several European countries, it became clear that breeding bird populations are hardly ever stable and may species wintering in Africa, including European Swallows, are declining. Apart from may short-term changes largely caused by variation in the weather, long-term changes are related to changes in land use and intensification of agricultural practices in Europe, and global climate change. Population trends in several species are linked to changes in rainfall patterns in the non-breeeding areas in Africa. These relations have been mainly established on correlations between rainfall patterns and population trends, and field data are lacking in many species. This motivated to study European Swallows in Ghana.

The project is a follow-up of studies by Van den Brink et al. (1998) in Botswana and Van den Brink et al in Ghana.

The field work concentrated on the following topics:

• Searching for concentrations of foraging or roosting Swallows.
• Catching of Swallows and other wetland-related songbirds with mistnets to collect data on age, biometrics and moult.

The three research locations were also sampled in December 1996 - January 1997 making a comparison possible between years. The overall weather pattern was different between both years. the end of the rainy season was normal in 1996, but much later in 1997, when heavy rains occurred until early December. This may have caused a higher food availability in particular early December 1997. In the report, study sites, methodology and results are presented, and a summary with conclusions on the following subjects:

• Age distribution
• Size and condition
• Moult
• Moulting strategy in Ghana
• Feather mites
• Other European passerines