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.

Wednesday 17th Oct. Decoy wood warbler works wonders!

Following last night’s rather stormy weather, we manage to find the tagged birds quite easily; bird “10” is in a surprisingly low bush, happily preening away, and the other two are also quickly located.  We wonder whether the lost tag from the 14th/15th may have made its way down from its suspected lodgings in that tree.  Using the radio receiver, it is very quickly pin-pointed on the ground – once again still attached to a pair of moulted tail feathers.  It does seem odd that these birds should drop their feathers quite so readily.  The Ghana birds, which didn’t arrive on site until well after mid-November last year, retained their tags until we left the site on the 13th of December, which was actually just after the start of moult witnessed in other birds in the area.
Our trapping effort with the mp3 playback is yielding very little, so we decide to try our wood warbler decoy one more time.  Oppong deftly straps it to a “branch” of a small “tree” (a fallen piece of brushwood) and then sticks this vertically in the ground right next to the net with the mp3 song playing.  Not really expecting much, after all the song alone is not working and the decoy has not appeared to work before, we are therefore surprised when 20 minutes alter Japheth returns from a net round with 3 wood warblers.  I’m not even sure I’ve seen 3 wood warblers in a net before – in fact, definitely not!  We colour-ring and fully process these birds, but we won’t be tagging any more birds for now.  We need to move on to other potential wood warbler sites in southern Burkina within the next week.  Ideally we’d like to get some gauge of the importance of the region as a staging post before the birds head further south to the more humid forest zones, in Ghana and beyond.
This evening Roger and Japheth report that one bird has apparently completely disappeared, and the other 2 are getting tricky to find!  Well, this rather brings our potential departure date forward!  The “vanished” bird’s tag was due to last well into next week.  If this is the case, then more exploration for potential wood warbler sites will begin over the weekend – but where should we go?  Time to consult some satellite images, and our colleagues at Naturama!

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