What are the non-breeding causes of Palearctic-African migrant declines?: Ecological studies of migrants in Africa

CONVENORS
Dr. Volker Salewski
Max-Planck-Institut für Ornithologie, Vogelwarte Radolfzell, Schlossallee 2, 78315 Radolfzell, Germany
Email: salewski@orn.mpg.de, Tel: ++ 49 (0) 7732 150119 , Fax: ++ 49 (0) 7732 150169

Will Cresswell
School of Biology, University of St Andrews, Bute Building, St Andrews, Fife, KY16 9TS, UK
Email: will.cresswell@st-and.ac.uk, Tel: ++ 44 (0) 1334 463010, Fax: ++ 44 (0) 1334 463600

DESCRIPTION
This symposium seeks to focus on current work on the ecology of migrant birds on their wintering or staging grounds in Africa that seeks to identify the specific causes of their declining populations, and so build on earlier work where general conditions such as rainfall or temperature on the wintering grounds have been identified as correlates of European population trends. In recent years it became obvious that amongst Palearctic breeding birds that trans-Saharan migrants have been especially affected by population declines. These declines are largely independent of phylogenetic relations, habitat preferences or ecological guild, although those species that winter in the dry zones in Africa seem particularly affected. A number of studies have correlated demographic factors such as annual survival or breeding success with conditions such as rainfall or habitat change in the non-breeding areas. However, the causal link between factors such as rainfall on population dynamics is often not clear. For example correlations may not necessarily indicate which factors limit populations, and cannot show where and when in the non-breeding season that they operate. This symposium aims to focus on the question of how populations of Palearctic trans-Saharan migrants are limited by specific conditions experienced in the non-breeding areas. It aims to highlight studies which show a link between the ecology of migrant species within Africa and population fluctuations or demographic parameters of the affected species. Such an approach is needed for a better understanding of the distinct declines of many species of migrants and any implementation of conservation strategies to include the entire annual cycle of migrating species.

KEYNOTE 1: Cresswell, W. 
What are the non-breeding causes of Palearctic-African migrant declines? Ecological studies of migrants in Africa.

KEYNOTE 2: Salewski, V., Tegetmeyer, C. and Flade, M.
Factors effecting population dynamics of Paleartic-African migrants in the non-breeding season – a case study of the Aquatic Warbler.

Bayly, N.J., Atkinson, P.W, Clark, J.A, Rumsey, S.R. 
Crossing the Sahara desert – could fuelling constraints in west Africa limit populations?

Grinblate, S.  and Strazds, M.
Preliminary report about the impact of DDT and other pesticides on breeding success of Black Stork in Latvia

Remisiewicz, M., Underhill, L.G. , Tree, A.J. , Gustowska A.  and Taylor P.B.
Extended moult as an adaptation of waders to the use of ephemeral freshwater habitats at their wintering grounds