The project

Our knowledge of ecology of migrants in their wintering grounds is extremely poor and severely hampers our ability to explain these declines and conserve this group of species. We lack even basic information about when birds arrive, the habitats they use and how they move around Africa.

The aim is to understand how Palearctic-African migrants use and move around the different vegetation zones found in West Africa, ranging from the semi-desert Sahelian region in Burkina Faso to the lush tropical rainforest in southern Ghana, and whether habitat change may impact them on their wintering grounds.

During the temperate winter of 2009/2010, using point count methodology and mist-netting, we recorded migrants along a degradation gradient at five different stations on a north-south transect. In 2010/2011 we plan to re-visit these sites as well as roving further afield to get a broader picture of migrant habitat use.

Burkina Faso: 8 October: Back to the species rich woodland

Phil Atkinson writes: Morning broke at 5.30 and the familiar routine of getting out of camp went a bit quicker than normal. A trip back to Gorom-gorom, the nearest town, had revealed 3 other holes in the spare tyre’s inner tube so with fully-inflated tyres, we set off north again. Not a stork in sight this time and we got to the sites with no trouble at all. It was a revelation – as the picture below shows, the habitat here was totally different to that near Oursi – many more species, no browse line and lots of migrants! Luckily, Acacias are generally good for migrant passerines but this habitat was stuffed full of Pied and Spotted Flycatchers, Melodious Warblers, Willow Warblers, Redstarts, Bonelli’s Warblers. It tended to be very linear in nature and occur in the bottom of the dune slacks although the slopes were very gentle so that it was difficult to work out that was low lying dune slacks and what was a ridge. It brought it home to me that the Sahel in Burkina at least is full of gently undulating slopes with fairly hard impenetrable soils so that when it rains water flows along the surface to congregate in the lower areas, making it suitable for woodland to develop.
After the revelation about non-degraded habitat, we move further north still to some very degraded habitat (above) and the contrast with other areas we had seen became clear. Large areas had been completely cleared and all that was left were stumps. We now had areas where we could put transects to make sure we covered different habitats as well as sample across a degradation gradient…

The satellite image below (courtesy Googlemaps) shows just how complex the vegetation is in this region. The dunes can be seen running east-west and the areas of species rich woodland can be seen at the bottom running along lines marking where water collects and runs off when it rains. Sampling this is not going to be easy!

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