The Gambia December 2011

December saw Lee and I heading off with 9 other British and Irish ringers to the Kartong Bird Observatory in The Gambia for an 11 day ringing expedition. The objectives being to learn more about migrant Western Palearctic birds on their wintering grounds and to increase the limited knowledge of West African birds.

Located on the coast, near the border with Senegal the habitat surrounding the observatory is a mixture of sand dunes, beach, mangroves, coastal scrub with pockets of remnant forest. The observatory itself overlooks a former sand mine, which during the rainy season fills with water. These pools contain extensive reed and rush beds which provide refuge, roosting and breeding sites for a huge variety and number of birds, along with the occasional crocodiles! Ours days involved mist netting in the mornings in one of these varied habitats, followed by setting new nets or more mist netting in the afternoon. After dark we would head out dazzling, using lamps to catch waders and nightjar.
Two evenings we headed for the beach, setting up nets to catch waders and seabirds, the first of which was particularly successful catching a number of sandwich terns including one that was ringed as a chick earlier in the year off Northumberland!
Setting tern decoys on the beach

Other activities including flick netting amongst the cattle for oxpeckers and whoosh netting for vultures.

In total we caught over 1200 birds of 121 species, and most importantly 250 Western Palearctic passerines, including birds we regularly encounter at home such as reed warblers, chiffchaffs and whitethroats and others that are more often seen on the continent such as the beautiful melodious and subalpine warbler. Other highlights for me included ringing my first nightingale and two of 19 woodchat shrikes!

 

As well as this we caught birds doing unusual moults, or what we think are unusual! With comparatively little ringing done here we are learning so much that seems odd but could be the norm! On this trip we caught a juvenile chiffchaff that was undergoing active moult (it was growing and replacing some of its flight feathers) and one which had obviously just finished growing its last three flight feathers. Now juvenile chiffchaff’s that breed in Britain undergo a partial moult (they moult body feathers but not flight feathers) before migrating south to the Mediterranean, North and West coast of Africa. They keep these old flight feathers all through the winter and during the breeding season back in Europe, before finally replacing them after breeding. So what were these chiffchaff’s doing? Recent work on the Iberian Chiffchaff (recently described as a separate species) indicates that some juvenile birds of this species moult some of the outer flight feathers during their post juvenile moult. However, this is usually finished by the end of September before they migrate south and one of our birds was still in active moult!! It must be remembered that little is known about the moult strategy of this species and just highlights how important the work of the Kartong Bird Observatory is!

Another interesting Western Palearctic species caught was an Eastern Olivaceous Warbler (North African race reiseria), which turns out is a new species for The Gambia.

Eastern Olivaceous Warbler – North African race reiseria

Of course we also caught a lot of African birds, which ranged in colour, size, shape and ferociousness! Once again we were at the cutting edge of knowledge for these species, every bird providing new information on moult, breeding…even identification!

Weaver’s presented a particularly difficult ID challenge, since they were in non-breeding plumage and needed wing and head measurements to identify them and with large flocks forming by the end of the trip, we needed all hands of deck to get them out of the nets!
 
Extracting over 100 weavers from the nets!

I particularly enjoyed learning about the long-tailed nightjar of which we caught 70 and the kingfishers. We caught 7 species of kingfisher ranging from the giant kingfisher to the African pygmy kingfisher, although my favourites were the pied kingfisher and malachite kingfisher with its rather funky hair do!

Pied, Giant and Pygmy Kingfisher
One of my favourites, the Malachite Kingfisher

All in all it was a fantastic trip and a huge thank you needs to go to Colin Cross and his wife Binta, our helpers Manuel, Moses, Dembo and Abdoulie, Hanni and the guys at Lemonfish for feeding us and putting up with having ringing equipment everywhere and constantly changing meal times! To Jez for organising the trip and for all the team members who helped make it such a wonderful trip!

Another account of the trip from one of the other team members, Sam Bayley can be found at his Blog http://horshamringers.blogspot.com/and includes a rather interesting encounter with 23 leeches!

Information on Iberian Chiffchaff moult can be found here http://www.ibercajalav.net/img/380a_IberianChiffchaffPibericus.pdf

Below are just a very small selection of a few other birds caught…

Lanner Falcon
Common Wattle-eye (female)
Blue-cheeked Bee-eater
Long-tailed Nightjar
Jacana
Little Bittern
Melodious Warbler
Squacco Heron
Grey-headed Bush Shrike
Grey Kestrel
Nightingale
Pied Kingfisher
Giant Kingfisher

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