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.

29th Jan – 8th Feb A massive team on the move!

The wood warbler team heads out once again to the forest zone to recce the area in the very south west of Ghana, around Ankasa national park.  With a team of 8, and for 2 nights 11, we need to be sure we can secure reasonable accommodation along an appropriate transect of sites from Ankasa northwards to Dunkwa, so the first couple of days are spent on this task alone!

Ethiopian Swallows roost at Dunkwa guest house

A Dunkwa eaterie - not the best advertisment for it!

With this achieved, we carry out our first survey at Cape Three Points, and next morning Ankasa, and in all this wonderful forest, we find no wood warblers.  The team of experts cannot arrive too soon!

Bamboo grove within Cape Three Points forest

The team surveying a clearing for power lines in Ankasa

Roger scanning a forest pond in Ankasa: "Is that a white-breasted kingfisher?!"
On the 3rd of Feb we are joined by driver Duncan, Dr Danaë Sheehan and Dr John Mallord from the RSPB, and Professor Tomasz Wesolowski from the University of Wrocslav in Poland. John has been the project leader on the RSPB’s UK wood warbler project since 2009, and Tomasz has been studying the wood warblers of the Bialowieza Forest in Poland for quite a bit longer than that!!  We return to Ankasa on their first morning, and lo-and-behold, we hear no wood warblers in a transect that starts about 300 metres in from the park entrance.
Tomasz, Roger, Japheth & John trying hard for wood warblers in Ankasa

Upon completion some 3 kilometres later, we head back to the exit  to try a few points of playback in the farmland immediately outside.  Whilst part of the team undertake the count, the keen-eyed Dr Mallord spots his first Ghana wood warbler in a flowering Ricinodendron, next to the river, right outside the park entrance. 
Farmland left, forest right, and (L) the solitary Ricinodendron home of our first Ankasa wood warbler

The recorders, not having seen the bird, then detect this individual themselves once they use the playback, when sure enough the wood warbler responds.  One further bird is found after 5 points in the farmland, and that’s after none across 30 points in 2 mornings inside the forest.

As we move north we are joined for a couple of nights in by Kasper Thorup and Anders Tottrup from the University of Copenhagen, and their driver and our old friend Emmanuel from GWS. With this enlarged team we split into two and cover twice the ground the next morning, in forest near to Tarkwa. Amazingly, the greater number of wood warblers is encountered in a large patch of plantain within one of the two forest blocks that we visit.

Roger & Japheth in farmland within "protected" forest - but it seems good for wood warblers
With this and our Ankasa experience in mind, we decide to change tactics the next morning.  After waving off Kasper an Anders as they head back to Accra, we set off for Nkonto Ben forest reserve near to Bogoso, again with two teams.  This time one team follows a logging track, and the other explores nearby farmland outside the reserve, so we can hopefully do more farmland points in one morning than we’ve managed before.  Although the forest team find 2 wood warblers during 4 hours and 3km of transect, the farmland team, walking along a road through very degraded looking habitat, manage 6!  Seeing as the  farmland is adjacent to forest, thoughts arise as to whether there may be a preference for this forest edge habitat.  We decide with our future transects to include “controls” away from the forest edge, at 5 and 10km distances.

On to Dunkwa once more (Whilst Danaë and John head back to Accra to meet with David Gibbons and Juliet Vickery, the rest of the team spend the next two mornings at Opon Mansi and Subin Shelterbelt forests respectively.  At the first site the team of Roger, Japheth and Tomasz find just 1 wood warbler in the forest (on the edge) and a few more in the farmland.  They also encounter a stretch which passes the awful mess created by illegal small-scale gold mining.  On our travels we come accross many of these eyesores, not only removing chunks of the forest, but polluting the waterways, and with scant regard for safety endangering the lives of those employed there.

Illegal open-cast gold mining

Meanwhile Oppong and I drive to and then walk Ikm transects at minimum distances of 5km, 7km and 10km from the nearest point of forest.  At none of these do we find any wood warblers.  Some of the habitat traversed is pretty intensive palm plantation, but there are still stands of trees here which one might think would support a wood warbler or two.  For example, in one spot there were 4 flowering Ricinodendron, the same species as was being used for foraging by the first Ankasa bird.  At Subin the roads are so bad that we cannot afford to drop of the team and then race around to the controls at 5, 7 & 10km, and then return to pick them up, so the team stays together to do 10 points in the forest then 5 in the farmland.  Again, the 5 farmland points yield more wood warblers than twice the length of transect inside the forest.  Once done, and now en route to Obuasi, we stop off at the 10km mark from nearest forest, and along 1km in quite badly degraded farmland we get no response from any wood warblers.

One of the many non-migrant highlights: dwarf bittern

Woodland kingfisher

Last leg back to Pepease, and we hear that Danaë, David, John and Juliet are already there.  Most amazingly, whilst waiting outside the accommodation for us to arrive, they are treated to good views of a wood warbler in one of the garden’s trees.  We near-residents haven’t even seen that!! There has been a melodious warbler around here a lot recently though……

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