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

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