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: Ringing Report from Oursi 21 Feb - 3 March

Tim Walker writes: We were in situ again from 21 February and ringed every morning until 3 March. The four major sites each had 2 consecutive sessions and at the end we tried a new site which was effectively a fruit orchard (growing a sweet tasting fruit called gib gib?). A line of 4 60’s and a 40 kind of reminded me of Icklesham in East Sussex (though obviously on a much smaller scale). We had to work hard here to keep up with catches - 119 (+1 retrap) in 2 hours on the first morning and 141 (+1 retrap) in just under 3 hours on the second (3rd March). This latter site could be one for the future.

Mohammed setting a net at the 'Oursi north' site

The 4 main sites yielded 299 birds (+43 retraps) over 8 sessions, which is a decrease on our earlier visit. However it has to be borne in mind that average net opening times were diminished due to rising temperatures. There is no cloud cover here and it is already hot by 08h30 or thereabouts.

87 (+12 retrap) migrants were trapped over the period comprising 14 species. Most numerous were Common Redstart with 19 (+3 retraps) with interestingly, all but two of these being males of varying age. So do females winter in different areas? Bonelli’s Warblers with 17 (+1 retrap), and Common Whitethroat with 15 (+1 retrap) were the next and the only other migrants to reach double figures. A pleasing total of 8 (+1 retrap) Woodchat Shrikes were trapped, as well as 8 (+1 retrap) Olivaceous Warblers. Some work needs to be done on the latter as more than one race is involved - we have various biometrics to scrutinise at a later stage! Other species included just singles of Chiffchaff and on the final morning, a male Willow Warbler. Reed Warblers started to appear with 4 caught in the last few days. Exotics (from a British point of view!) were 3 (+2 retrap) Hoopoe; 5 Subalpine Warblers; 4 (+2 retrap) Orphean Warblers; a male Blue-headed Wagtail, and a cracking full adult male Black-eared Wheatear.

A further example of site fidelity involves the only Wryneck caught to date this year. Ringed on the 24th Jan, it was retrapped the following day from the same net. Amazingly it was caught again in the same net on the 22nd Feb when it was 2 grams heavier than previous captures.

I shall close on another raptorial note! A Gabar Goshawk is one thing, but an immature female Dark Chanting Goshawk is quite another. Hopefully the photo will give an impression of its formidable size. The wing length was 308 mm and the weight an astonishing 670 grams!

I should also mention that the lake at Oursi is a Mecca for waterfowl, with White-faced Whistling Duck and Knob-billed Ducks being the predominate species. But that is not to say that species such as Garganey are not also abundant, and to see upwards of 100 birds in a day was not an unusual sight. Being interested in waders as I am, I was keen to find Black-tailed Godwits, and the highlight must have been the 107 birds on the 23rd Feb (though these numbers had reduced to just 8 birds by the 4th March). These are of the nominate Dutch Limosa limosa race, but, try as I might, I could not track down a single colour marked individual. I also scanned the many Glossy Ibis, again in vain, for colour rings. Sacred Ibis, 3 Black-Crowned Cranes and many many Wood and Green Sandpipers, Ruff, and the odd Marsh Sandpiper were also notable.

On Sunday we head back to Nazinga for our final session. Hopefully we can improve on the solitary Redstart we caught last time. The final Nazinga report may well be written back in the UK!

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