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: Update from Chris, Tim, Mohammed and Daniel 5th March 2010

Chris Orsman writes: Even after just 2 weeks since we were last here, there’s a perceptible change in the lakeshore landscape. With water levels slowly dwindling, what remains of the grass near the lake is drying out, and receiving ever greater pressure from livestock. In places the former shoreline and dry hollows resemble the dune expanses of the “machair” of parts of Scotland, but without the greenery, and a lot more dung!
Danae and Phil at the lake in October 2009:

...And the same spot 4 months later in February 2010:

There hasn’t been any great change in the mix of migrants present, but a notable change in numbers (or detectability!) of some species. Whilst the ringing team caught a few Subalpine Warblers, the transect surveys struggled to pin many down, and only 2 were noted, compared with 30 last time! Despite the fact that these birds are about to head off to breed, those that were spotted and watched outside of the transects were largely silent, whereas many were calling or singing in January. Are they less concerned with winter territoriality at this stage?
Bonelli’s Warblers are again vocal, but their numbers appear to have dropped. It may be a measure of the further desiccation of shrublands away from the lake, where we continued to record these birds last time, but largely absent in February.

Bonelli's Warbler:

Olivaceous Warblers were almost absent during transects this time around, but the odd territorial bird was noted during the visit, including one during the whole-area-search on 3rd March. No Orphean Warblers on transects at all this time, and local warbler species not as evident either. However, a Desert Cisticola to the north on the 28th Feb was a welcome new species for the project.

Although more Barn Swallows and Red-chested Swallows were seen during the stay, very few were recorded during the transects. Away from the transects, however, “flava” wagtails have been seen in small flocks of up to 50. Hoopoe numbers have dropped, and whilst Woodchat Shrikes have remained stable, some of them have shifted habitat slightly. More of them are venturing into the denser wooded areas nearer the lake, and can also be found hunting amongst the lakeshore livestock.

Woodchat Shrike:

Also on the shoreline, and on several transects, a more than decent representation of Northern Wheatears once again, despite hearing the first early reports of some arriving back in the UK! Some of the males are looking really smart pre-breeding, and challenging the few Black-eared Wheatears for the “Top-Chat” title. Having said that, the male Common Redstarts take a lot of beating, and although few were seen on transects, our whole area search around the east ringing site yielded 7, with 4 practically together, one of them unsurprisingly ringed, and no less than 10 days earlier!

Common Redstart outside our accomodation in Oursi:

The most dramatic change has been the rise in Turtle Dove numbers, and suggestions that these latish European arrivals may actually be on the move. Whereas on previous visits they were relatively abundant in favoured roost habitat, they are now much more widespread, and have been seen on all but one transect. They’ve even been in the driest habitats some kilometres to the north, and the occasional flock of 100+ have been seen moving north from the lake during the evening. Further to this, these supposedly silent birds have at times been heard calling. During the whole area search, a single Turtle Dove was flushed from a lone acacia shrub, and amazingly a nest with egg was spotted. Perhaps coincidence that another dove species was nesting there, and I know not what a Laughing Dove nest looks like, but how I wish I’d taken a picture of said nest for others to see! When we went back at the end of the survey there was no bird to be seen. Conditions for feeding here appear to be favourable, but is it actually possible that a Turtle Dove could nest in Burkina? Fantastic news comes in the form of our ever helpful Oursi colleagues, Aly and Omar, who are going to be able to join us at Nazinga for our final 2 weeks. Extra help for us (maybe more nets to catch a few more migrants than last time?), but also fantastic training and experience for them we all hope! Once again, it has to be said the elephants will play their part, as they will be new species for the lads. Can’t wait!
Sunrise at the start of a transect in Oursi:

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