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.

11 -17 February: A second bird with a geolocator!

Week two had a slower start with the catch from the northern nets dropping, so the group changed the set-up, adding nets to the eastern fork of the north site, and another line of nets further towards Nsoatre village to the north east to target three Nightingales fitted with geolocators in 2012. Three Nightingales were caught, but all new birds.

The habitat around all of the sites has changed due to agricultural practises, but the north east is very rapidly being turned into farmland, with just a narrow band of scrub now. The locations of the caught Nightingales are being recorded to help us target new birds, and provide information on winter territories to inform future work at the site. If the amount of available scrub habitat is decreasing it will be interesting to see whether the Nightingales will simply choose to live in denser populations or move elsewhere. Radio tracking and recording the birds precisely will help to monitor this. It is also relevant with regards to looking for the geolocator-tagged birds, our only choice is to spread the nets over as wide an area as possible covering the areas birds were previously caught in. If only there was a geolocator magnet!

Over the 11-16, the long standing north nets had proved disappointing, and the targeted Nightingales stayed put - no doubt laughing to themselves. The ringed Nightingales seem to be harder to catch than unringed birds. Perhaps they have learnt the net locations. A few afro-trop species have kept it interesting with both African and Red-bellied Paradise Flycatchers and Tambourine Doves.

The location of the other geolocator birds is still unknown however, despite listening for calls, there seem to be fewer birds than in previous years. We are aiming to target all Nightingales we detect at the trap sites if possible. Although all the birds are understood to return to the same location each winter and therefore should be able to be caught at that same location, the dynamic nature of the habitat, combined with human influence such as agriculture and intra-specific competition with other Nightingales may mean they may have moved to other locations. Determined to get a better result on the Nightingale front, the group targeted another bird on the central northern track on the 13th February near where a geolocator bird had been tagged in 2012. This resulted in a last minute flurry of birds at dusk including a new Nightingale, three Garden Warblers, a Reed Warbler and Melodious Warbler. The last-minute rush, although welcome, made us late for dinner (typical as we were planning to finish early), finally meeting the RSPB Wood Warbler team, Chris O, Roger, Japheth and Oppong at the guesthouse just over an hour later than planned. Eric laid on a fantastic buffet of Ghanaian food for us. Having eaten only very basic food the look of disbelief on their faces was priceless, convinced they were now in heaven!

Clockwise from left: John, Roger, Vicky, Japheth, Nick, Chris O and Oppong. Out-of-shot: Eric slaving away in the kitchen (Mark Hulme)

After a lovely evening of catch up, good food, beer and football it was back to business.

A few moderate ringing sessions followed on the north side consisting mainly of afro-tropicals such as Little and Baumann’s Greenbuls, and a few Palearctics. With a waning catch it was decided it would be more productive to move the nets completely and try again on the north side later after a break, to coincide trapping with the time of year the birds were caught last year and to allow the birds to get used to moving freely across the tracks again.

Afro-trops included- Tawny-flanked Prinia, female Red-shouldered Cuckooshrike, White-throated Bee-eater and a new Snowy-crowned Robin-chat. The ‘bush’ Nightingale on the main northern net ride was proving to be a slippery character, so a small net was erected between its favourite singing-post inside a bush, and with a bit of persistence, the Nightingale was caught on the 15th and found to be another new bird.

With quite a lot effort in the heat and high humidity, all the northern nets were taken down that day and new net rides set up on the south side of the Ivory Coast road, to rest the north side and attempt to catch the southern site Nightingales with geolocators. To avoid the intense heat the group, rather romantically, have set up camp amidst the plantains where there is some shade for processing birds. The new nets performed particularly well on the first catches on the 16th with 14 new Palearctic migrants. Two retrap Reed Warblers, one from the same week and the other ringed in March 2011, a new Reed Warbler, one retrap Garden Warbler from March 2011 (more about which later!) and three new Garden Warblers, one Whinchat, one retrap Melodious from November 2011, one Red-necked Nightjar (potentially a wintering range extension and an unusual species to record), 2 new Nightingales and 2 retraps, one with a geolocator! The second so far! They were originally ringed in October 2011 and mid February 2012 respectively.

Second Nightingale with geolocator caught in 2013 (John Black)

Red-necked Nightjar (Vicky Gilson)

One of the Garden Warblers, quite amazingly, was the same bird that had been ringed at Nsoatre in March 2011 by Mark, retrapped and fitted with colour rings in February 2012 by Roger, a committed volunteer of the BTO and RSPB projects (and in the presence of Nick) at the same site, and then controlled twice in Kent in June and July 2012 by John and Vicky at their Nightingale Retrapping Adults for Survival (RAS) project site before finally being processed again in Ghana by Mark and John. John, quite understandably was ‘over the moon’ at seeing P007049 again. Read about John and Vicky’s discovery in Kent at the Demog Blog.

Mark and John with Garden Warbler (Vicky Gilson)

The 17th was rather windy preventing a catch like the previous day, although ten migrants were caught thanks to three additional nets placed for Nightingales, thankfully these included one new Nightingale.

Luckily a Yellow-browed Cameroptera, Common Fiscal, and Red-winged Warbler made a quiet session exciting none-the-less. As it was a Sunday the team had a much needed afternoon off from field work, catching up with data inputting, and enjoying much needed cooling beers.

Looking back at previous ringing data the group have processed 104 migrants, 16 of which were Nightingales, of which 4 are retraps. Afro-trop retraps have also proved to be interesting, and will help inform survival studies. A few records from previous years include: a Yellow-browed Cameroptera ringed in February 2012 and a Green-headed sunbird from March 2011.

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