Migrant birds in Africa: 30th-31st March

Mark Hulme writes: After some valuable data had been collected at our most productive site we headed north to Bui National Park once more. We were hoping to see if reports that Bui might be an important passage site for migrants on the move in late March were true this year. Bui is currently undergoing some changes as a large Chinese-funded hydroelectric dam is being built down-river, one advantage of this is that roads leading to Bui are now excellent so we made good time! On the way into the park we also saw a splendid male Patas monkey, one of the few monkey species to thrive in the dry savannas. After securing the services of a guard we headed in to the village where we set up camp amongst a large group of curious children and hungry sheep and goats. There was no electricity so the football friendly between England and Ghana had to be followed by noting the reaction of people listening to their radios. It was pretty obvious when Asamoah Gyan scored a last-minute equaliser for Ghana by the spontaneous round of applause!

The following morning we split into two groups with Alex and I taking one route and Nat and Tina the other. We had limited success, with quite a number of Pied Flycatchers and not much else migrant-wise but Nat and Tina also had some Willow Warblers and a Garden Warbler or two. No Wood Warblers, unfortunately. It was interesting to see the variety of species in the riverine forests though, including Leaflove, Square-Tailed Drongo, Puvel’s Illodopsis and African Finfoot (seen by the guard, not by me unfortunately!) as well as White-headed Lapwing on the sandbanks. In the afternoon we decided to have a closer look at the forest bordering the river by taking canoes up the Black Volta into the park. No passerine migrants were detected but there were a number of Common Sandpipers and Wood Sandpipers along the river and plenty of kingfisher species, egrets, herons and Sengal Thick-knees to keep us interested. Oh, and the hippos……8 seen in total including one right where the fishermen keep their canoes. The fishermen told us that they have to leave the village to be re-housed in a purpose-build “new town” in May, and the park manager informed us that the water would start rising in June in preparation for the dam to become operational in 2013. This will inundate the riparian forest and flood much of the grazing land the hippos depend on, presumably reducing their population considerably, which currently stands at around 500, by far the largest population in Ghana. If the forests do ultimately provide passage habitat for species such as Garden Warbler and Wood Warbler this may also affect migration routes as well, but that would be extremely difficult to quantify. We just hope that the effect on the park ecosystem will be less extreme than we fear as there is no turning back now. After one more night in the village we left this beautiful place wondering what the future would bring.