We assessed the assemblages of birds inhabiting pine-dominated managed forest, aged between 1–5 years and above 140 years. Birds were counted on study plots representing eight different phases to the forest's development, with nesting, foraging and migratory guild categories recognised. Numbers of bird species and population densities, both increased markedly with stand age (respectively r = 0.988 and r = 0.936, P < 0.001). While numbers of ground-nesting bird species failed to correlate with stand age, successively older stands did support ever-greater proportions of species in the assemblage that nested in tree crowns (r = 0.976, P < 0.005) or tree holes (r = 0.833, P < 0.005). Raptors were most abundant in forest at the oldest stages of growth, and there was an age-gradient-related increase in the shares of both plant-eating species (r = 0.952, P < 0.005) and raptors (r = 0.764, P < 0.005). Resident birds were most numerous in the oldest forest. PCA for ten selected variables (relating to guil...