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: Nazinga 05/02/10 – 18/02/10

Chris Orsman writes: Back in December, our last spell in Nazinga, much of the landscape was charred following the burning of the savannas. What has changed is that so many of the once sorry looking trees and shrubs are now bright with new growth, and whilst many taller species are fruiting, yet more are now in flower.

Much more obvious than last time are the Scarlet-chested, Pygmy and Beautiful Sunbirds, busy about the flowering shrubs and very vocal defending territories. Alongside these, the local warblers are out in force. Tawny-flanked Prinias seem to be everywhere, as are the Grey-backed Camaropteras, and more than one large cisticola (Croaking or Winding – I’m still not too sure!) but most noticeable are the Senegal Eremomelas, like the sunbirds, now highly vocal and territorial. Something about the habitat has improved post-fires.

The first of the few migrants encountered was a sole Northern Wheatear, on our first transect outside of the ranch on nearby farmland. During all the 3 “farmland” transects, the dry weedy stubbles didn’t appear to be supporting as much as on previous visits - perhaps supplies are exhausted – but the lack of Whinchats and just one Tree Pipit was made up for by a scattering of Woodchat Shrikes, a couple of Emin’s Shrikes, and at least two breeding pairs of Hueglin’s Wheatears.

Our first transect back within the ranch transect has altered beyond recognition, as it passes through a research zone that is not supposed to be burnt. A fire broke out here in January, and at this late stage the grasses are that much drier than early December. As it was accidental, no one was on hand at first to control it, and it spread like, well, you-know-what! It also drastically changed one of our ringing sites, so much so that all the net rides were very open, and we considered moving to a new spot. Walking through this habitat promised little, but amazingly, it is now alive with even more Hueglin’s Wheatears than the farmland. This late burn of old grassland clearly favours them, as they weren’t recorded in any of the other earlier-burnt areas.
On the first woodland transect, the first Pied Flycatchers were seen, albeit just 3! We did elsewhere see least 3 other individuals, but not one more on any other transects. Even our “whole area search”, which centred on some very promising habitat, failed to uncover any others. Compensating for this was the now more visible Swamp Flycatchers, Pale Flycatchers and Senegal Batis.

As for the mystery of the Willow Warblers, almost entirely absent in December, they remained non-existent at Nazinga, until our 9th day. Early on two successive mornings, a handful of individuals either called or sang, but very briefly. In November, they were abundant and singing almost all morning, behaving as leaf warblers should, foraging in the fine extremities of tall, birch-like trees in full leaf (will endeavour to find out the species for next time!). By December, the leaves had browned or fallen. These trees remain largely bare in early February. However, a close examination of a few specimens shows that these are producing new growth, and that this in turn is already supporting invertebrates. Could the first few Willow Warblers be the vanguards of some hoards which will arrive in time for a full canopy in early March?
Green and Common Sandpipers have been seen about lake shores almost daily, and occasional “flava” wagtails, Barn Swallows and a few Sand Martins. A single Black Stork was also recorded.Onwards to the Sahel once more, where temperatures we hear are soaring! How will the birds cope? Will our nets survive the livestock? And most curiously, will Tim eventually turn into a chicken after eating nothing but poulet for 2 months?

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