I joined the RSPB team working on the ‘Migrants in Africa’ project in Burkina Faso in November, providing support for the ringing operations. The project, jointly run by RSPB and BTO with support from Naturama and the Ghana Wildlife Society, operates transect surveys in parallel with ringing sessions at five sites from Oursi in northern Burkina Faso southwards to the coast of Ghana. The aim of the project is to understand how Palearctic-African migrants use and move around the different vegetation zones found in West Africa.
A round of ringing and surveys had previously taken place at Oursi in October, and I arrived in time to join the second round in the second half of November. Rains had stopped, being well into the dry season, and nights were starting to get cooler. We had four main sites for the ‘protocol’ ringing, and performed extra-curricular ringing activities when opportunities arose. Western Bonelli’s warbler was the most commonly caught European migrant during November (32 birds), followed by olivaceous wabler (15) and common whitethroat (14). Eight yellow wagtails were caught during two extra ringing sessions on the lake edge prior to evening roost. The number of turtle doves surveyed on transects crashed from 150 to 17 between October and November, although we still managed to ring seven in November. Smaller numbers of the following migrants were caught and ringed: subalpine warbler, common redstart, woodchat shrike, rufous scrub robin, northern wheatear, western orphean warbler, wryneck, European hoopoe, chiffchaff, black-eared wheatear and masked shrike. The only migrants recorded during transect surveys that were not captured during ringing sessions were one willow warbler, two barn swallows and one Montagu’s harrier. During November, just over 25% of all birds caught in Oursi were migrant species, compared with 2% at Nazinga, the southern study site in Burkina Faso.
The project is still in its early days, and the precise protocol is still being refined. Oursi appears to have been the most important of all five study sites for migrant numbers and range of species during October and November. It is interesting to note there was almost no overlap in the range of species caught and ringed in Oursi compared to elsewhere, melodious warbler being the exception. In comparison, the predominant species captured in Ghana were pied flycatcher and willow warbler, along with a few garden warblers and nightingales.
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