The purpose of this project is to integrate data from long-term detailed demographic studies of spatially structured bird populations across Europe. By doing this we hope to give an empirical foundation for the development of realistic models for the dynamics of spatially structured populations, in order to evaluate the consequences of habitat alterations and develop some general guidelines for management of endangered or threatened birds. In addition, field experiments (with particular reference to density-dependence and dispersal) are carried out in order to test critical assumptions of the models under consideration.