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.

26th Jan: A tot up

Nightingale Team: Our third morning in succession, ringing in the eastern patch produced yet another Nightingale. So a nice cluster of four new birds to radio track from now on in this area. One Snowy-crowned Robin Chat was a new bird for the totals. As a resident and potential competitor to the Nightingales (work by Peter Jones has previously suggested that Nightingales are interspecifically territorial and move south within West Africa at the same rate during the dry season) this individual was radio-tagged too, to provide information about its movements relative to the neighbouring Nightingales.

A low overall catch grave me a chance to do what ringers do and tot up the migrant score in the 10 days since my arrival on the 16th Jan, so here goes: Garden Warbler (40), Reed Warbler (10), Nightingale (7), Melodious Warbler (5), Willow Warbler (4) and one each of Grasshopper Warbler, Blackcap, Common Whitethroat and Great Reed Warbler; 70 individual migrants in all; 57% Garden Warblers. According to the field guide, several of these species are well out of range here close to Berekum, especially Grasshopper Warbler! The Melodious Warblers are among the personal favourites for Vicky and I since this is not a species we bump into every day in the UK

The Afro-tropical species number 49 from 10 species, plus one or two released immediately when we are pressed for time, so perhaps 50:50 ‘residents’ to migrants? Whatever, the ‘volume’ of migrants is an interesting reminder that here too the composition of the bird fauna is dramatically altered by their arrival or departure, in manner we are entirely used to in Europe in summer.

Posted on behalf of Ian

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