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: 1st December. An update from the last two weeks at Oursi

Chris Orsman writes: Since the last update all of the pre-Christmas transects and ringing have been completed at Oursi (we have two more visits after Christmas). Whereas last time we reported that there were fewer Whitethroats than in late October, we have since found them hiding 13km to the north of la Mare, in habitat that was chosen for the study as there were large areas of bare ground, degraded by livestock and wood removal. However this is interwoven by ribbons of at-times dense forest (although with a low canopy), formed where there are almost indiscernible shallow valleys where rainfall collects after running off the otherwise unyielding soils. A ringing site set up here in conjunction with the transects also trapped numbers of Whitethroats that had been absent elsewhere. Seems as though this is their preferred habitat at the moment, and some of them have been sub-singing quite vociferously, but it remains to be seen if this is maintained once the deciduous species have shed their leaves. This is also the best area we’ve found for Rufous Scrub Robin!Lately too Wheatears have become more in evidence, and although primarily Northern Wheatear, have most recently included our first Black-eared Wheatear, and, dare I say, it a “possible” Isabelline Wheatear! Rosemary thinks so! Happy to agree but not 100% from my views of it!!

Subalpine Warblers still present and occasionally singing but mainly around the lake or with a km or so. Bonelli’s warbler numbers continue to surprise, with birds calling and singing, sometimes from isolated shrubs in very open habitats. Even right up to the end of our 16 days at Oursi, there was an Olivaceous Warbler singing in the tree nearest to the camp at Oursi, but very few were pinned down on the transects themselves. The camp individual was at one point joined by a Subalpine Warbler, a Bonelli's Warbler and a Redstart, all in the same tree.

There are still good numbers of Turtle Doves exploding from lakeside scrub early morning, but not the 100's that were around a month ago. Woodchat Shrikes continue to be present in some numbers, whilst Southern Grey Shrike numbers seem to have increased, perhaps with the more local movement of birds from the Saharan zone. Hoopoes are more numerous than in October although numbers may have dwindled slightly since mid-Nov. We are all still struggling to determine the race of these (both African and European Hoopoe occur here), so sadly not all records will be of European birds.

Perhaps surprisingly, there are still not many hirundines! The ringing summary however should indicate that there were enough Yellow Wagtails around to attempt a roost catch with a tape, with moderate success. Lack of experience of larger pipits means that only 2 of 3 seen on transects could be identified with certainty. Wish I’d had a nice long lens on the camera for the third!

Other regional migrants have largely disappeared, such as the White-cheeked Bee-eater, whose numbers were increasing at our last visit late October, but are largely absent now. In early November we had begun to see them at Nazinga, so perhaps larger numbers are to be found there in the next couple of weeks. Highlights from the Mare itself include mostly things I didn’t see (!), including apparently 1000's of Collared Pratincoles (before our return to Oursi), Caspian Tern and Osprey. Numbers of Garganey are slowly rising, and many more Ringed and Kittlitz’s Plovers are making the most of the ever-larger expanses of grazed lake margin as the water recedes and the dung piles up! Marsh Harriers have been almost daily.

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