Species/habitat relationships and their responses at different scales are i
mportant aspects of ecological and conservational research. We studied the
occurrence of hazel grouse Bonasa bonasia males in a forest reserve over a
10-year period at varying scales and population densities, using two sets o
f habitat descriptions. Avoidance of pine Pinus sylvestris was the only hab
itat effect in the hazel grouse/habitat analyses that was significant throu
gh all scales, seasons and densities. Thus, in spite of long-term data on a
well-known species and detailed vegetation descriptions, only a few clear
patterns relating to hazel grouse habitat selection were found at the relat
ively small scales analysed. We conclude that the non-significant relations
hips were due to the generally suitable composition and small variation of
habitats within the study area, and that significant results may not be exp
ected within the scales analysed and with the methods used. Thus, to find a
ssociations between animal species and habitats, a suitable study area must
include a certain degree of habitat variation and the relationships should
probably be examined at a scale equal to or larger than the home-range of
the species in question, or considerably larger if population data are avai
lable. The results are discussed in relation to other studies and the appli
cability of the habitat descriptions and census techniques for conservation
of hazel grouse populations in managed forests are discussed.