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.

18th March, Brenu Beach - Fieldwork drawing to a close

Mark Hulme writes: We are into the last couple of days of fieldwork in Ghana for this winter season and I walked the last transect this morning so thought I’d post an update of the results of the last few weeks transects since Damongo before it all gets a bit hectic with preparations to leave back to the UK on the 22nd of March.

Kogyae was very interesting with a little more mud on the terrible road and a little more burning having gone on since we last visited, particularly in the reserve, which was blamed on poachers who had been subsequently arrested, opening up the understory of the dense woodland there. Much of the previously burnt ground was regenerating as in Damongo further North. 24 Pied Flycatchers were seen or heard compared to 15 on the previous visit, perhaps indicating that numbers have increased slightly or the birds have become more detectable, possibly some birds had moved into the more recently burnt woodland from elsewhere. 12 Melodious Warblers were recorded, 6 of them singing, as was also common in Melodious Warblers in Damongo, compared to 8 recorded with one singing last time. Five Tree Pipits were seen, whereas none were recorded last time and 6 Whinchats (looking rather grand in fresh breeding plumage) compared with 12 last time, which may indicate a decrease but the numbers were small enough to be unsure of this. Some points with Whinchats recorded previously did not yield any this time but a snap-shot point count does not necessarily mean all birds in the vicinity were recorded! Interestingly, though, slightly fewer Whinchats were also recorded in Damongo. 12 European Bee Eaters had turned up since last visit, 8 House Martins were on transects with a flock of 30 plus also seen near camp and, most strikingly of all, 58 Willow Warblers recorded, most of them singing, compared to 30 last time when no song was heard at all. One transect on the penultimate day produced 21 Willow Warblers in open scrub and teak with scattered large trees, compared to 8 last time. Surely this is either indicative of either a recent influx of new individuals or higher detectability due to increased frequency of vocalisations, in either case it seemed like they were preparing for an imminent journey. Some extra bonus migrants in Kogyae included a female Short-Toed Snake Eagle, an immature Peregrine Falcon and a single Barn Swallow.

Ringing at Kogyae was also very interesting with 20 new migrant birds caught and 3 retrapped from previous visits, all at the one ringing site outside the reserve, compared with around five migrants caught at the same site in February. Ringing effort was higher this time due to two ringers being present, with 3 mornings compared with 2 last time and 2 afternoon sessions catching one migrant each, but it does seem that relative catches of migrants were up. In total 8 new Melodious Warblers were caught, suggesting that the transects in the Kogyae habitat underestimate their numbers, with one retrapped from January. 6 new Willow Warblers were caught, some using a tape-lure, as well as 3 new Pied Flycatchers, 1 carrying a lot of fat, and one from December. 1 new Nightingale and 1 from December with much fat, 1 new Spotted Flycatcher and 1 new Garden Warbler rounded off the migrant captures.

Melodious Warbler, Kogyae

Pied Flycatcher, Kogyae

Nat recording habitat data on a point count, Kogyae

Charcoal burning - a common occurrence in Kogyae

After a day or two in the capital, Accra, we were off to Kakum again, in the forest zone about 25 km inland from the city of Cape Coast. There had been slim pickings previously as far as migrants go on the five transects here and not a huge amount had changed this time, though a few Barn Swallows had been joined by a small number of European Bee Eaters over the plantations on the edge of the National Park, common swifts were not seen in contrast to 32 seen flying (of course) on the previous visit. One transect did throw up a couple of House Martins, a foraging Willow Warbler and a Spotted Flycatcher flycatching what must have been a stick insect, it isn’t nesting here like Chris O’s turtle dove is it? I very much doubt it. Otherwise a Melodious Warbler seen at the new ringing site was the only other migrant confirmed. Still no definite Wood Warblers, sadly. No migrants were caught over 3 mornings ringing, 2 at a brand-new site since the CES site has mostly been cleared to make way for a new plantation, despite close to 200 birds being caught in total. Some of the highlights of those caught included Western Bluebills, White-Tailed Alethes and a White-Crested Hornbill with a tail almost as long as Steve is Tall……

Plantation and forest at the edge of the National Park

Clearing net rides in the rain forest is hard work!

The Ringing Base at the new Kakum site - Tina, Steve and Rachel

Blue-Billed Malimbe, Kakum

Beautiful Brenu Beach (where I’m again very happy to be writing this blog from) has revealed 3 Spotted Flycatchers on one transect in rather open scrubby habitat a little inland, compared to one seen off-transect in a cassava field last time. Have they been here all along and switched habitat later in the winter as other habitat became unsuitable or have they moved in from elsewhere in the past month? It seems a little dryer here than last time. One Whinchat was viewed on transect and one off-transect, two were also recorded previously. No Garden Warblers or Nightingales have been recorded on transects but one of each have so far been caught during mist-netting, the Garden Warbler with little fat and the Nightingale seemingly fattening up for migration, as well as one Melodious Warbler, so very recent reports further North of possible passage of Nightingales and Melodious Warblers may well be true but not all have yet moved on.

Tourism on the coast is developing at break-neck speed and some coastal scrub has already been cleared even since our last visit. A nice-looking patch of scrub next to our constant-effort ringing site has been ear-marked for a new resort so this valuable habitat for Nightingales and Garden Warblers is certainly under threat at the moment, making it all the more important that we find out soon how habitat change may affect declining populations of wintering migrants. It’s been a pleasure to have been in Ghana working on this project over the last 10 weeks or so and I’m looking forward to looking at the whole dataset for these last two visits. The thanks, of course, must go to Chris Hewson for becoming a father leaving me to step into his fieldwork shoes (not literally you understand) – congratulations Chris!

Tina with a Pied Crow, Brenu

The Transect Team - Nat, Tina and Mark

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:

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!