A histogram of F. lugubris nest density and exposure. The frequency distribution of the nest number recorded at any particular direction is represented by different colours. For better visualisation, zero values are excluded.

  Part of: Antonova V, Marinov MP (2021) Red wood ants in Bulgaria: distribution and density related to habitat characteristics. Journal of Hymenoptera Research 85: 135-159. https://doi.org/10.3897/jhr.85.61431