Skip to main content
SLU publication database (SLUpub)

Research article2007Peer reviewed

Seed crops of Norway spruce and winter habitat quality for boreal birds: old-growth compared with managed forests

Sjoberg K, Pettersson RB, Ball JP, Sundstrom T


We compared the winter bird community in 5 old-growth coniferous forests and adjacent managed forests in northern Sweden. Norway spruce seeds on snow (available to birds) were sampled during late winter and differed about 13-fold between 1990 and 1992. There were no significant differences between the old-growth and managed forest in the seed-rich (mast) year, but during the seed-poor (normal) year there were more birds in total, and more birds belonging to the biogeographical group Northern taiga species in the old-growth forests. Our analysis suggests that differences in habitat quality between old-growth and managed forests may be small in the rare years with high spruce seed production, but in an average year, old-growth forests seem to be better for wintering birds. This pattern, although needing further study to determine its generality, is consistent with suggestions that forestry may negatively influence the avian community by reducing winter habitat quality

Published in

Annales Zoologici Fennici
2007, Volume: 44, number: 6, pages: 486-495