Why should Black-tailed Godwits still winter in West-Africa if Southern Iberia is just as good?

Black-tailed Godwit Demographic Project In November 2014 the University of Groningen, in cooperation with Global Flyway Network and financially supported by Birdlife Netherlands, embarked upon a 19 days expedition to the wintering grounds in West-Africa. We aim to set up a demographic research project in this area. Most important goal of this mission was to get a good overview of the wintering grounds, resighting conditions, local facilities and knowledge and to make a start with setting up a dataset of individually recognizable godwits that winter in West-Africa. Secondly we made a pilot study of habitat choice, prey choice, energetics and time budget. At this moment comparable research is done in NP Doñana (Spain), Extremadura (Spain) and the Tejo/Sado estuaries near Lisbon (Portugal). The last two are used as stop-over sites in February. We aim to continue our research at all these locations to find links between wintering sites, stop-over sites and breeding sites