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.

Monday 12/12/2011 The harmattan blows in

Above photo: harmattan "smog"

There’s a definite change in the air this morning. Driving down to the site as the night-time gloom lifts it becomes obvious that the visibility is not what it should be. We attempt to track the two birds and carry out a site survey. Shortly into the survey, and a single wood warbler (unringed) is spotted. A half hour later, and we hear the call of the first willow warbler for this site this winter, and a little later another wood warbler calls from the near distance. Further on still and a 30m Ceiba tree is host to single spotted and pied flycatchers, single melodious and willow warblers, plus 3 wood warblers – an extraordinary tally. The feeling already is that there are (suddenly?) more birds around than a week ago.

Above photo: 30m+ Ceiba tree, home to lots of migrants

A further 6 individual unringed wood warblers are seen, so 11 in total, plus we manage to trace our tagged birds 2 and 3, still a strong signal from both. 2 nightingales, a spotted flycatcher and a melodious are also detected later on. Throughout the morning, though, the sun fails to break through the haze, a dry, dusty and smoky suspension brought in by the arrival proper of the harmattan winds. Could it be that some of the migrants have also arrived with, or just ahead of, these winds?

Of interest whilst doing the rounds was finding a couple of trees who's bark had been slashed, apparently to harvest the medicinal sap. Plenty of ants and a few other bugs were making the most of the oozing resin.

Above photo: ants profiting from medicine harvest

Communication from Bee at Nsoatre; they arrived back in good time last night to track the nightingales. It seems – not surprisingly – that their bird 1 has vanished. We think that most likely here is that the tag has finally failed, as this was caught around the 10th of November. The other birds are present, but one or two others’ tags may be showing signs of weakening.

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