title: Interspecific competition and the structure of bird guilds in boreal Europe: the importance of doing fieldwork in the right season.
abstract: Bird studies have gained a central role in the debate on the importance of interspecific competition in nature. Thus, the negative results reported from a breeding bird community in a North American shrubsteppe area have created ripples throughout community ecology. However, the set of coexisting breeding birds might be an inappropriate operational definition of a bird community, because the intensity of interspecific competition can be expected to peak in autumn-winter. A review of North European data on wintering birds suggests that the case for the competition theory remains strong when bird communities are defined on the basis of winter coexistence.
authors.affiliation: Lauri Oksanen is at the Dept of Ecological Botany, University of Umeå, S-901 87 Umeå, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Oksanen