INVESTIGATING ANIMALS’ RENEWABLE BIOMASS USING A TREE-FITTING MODEL

C. Vlachos, K. Kitikidou*, D. Bakaloudis, M. Papakosta and E. Chatzinikos**

Aristotle University of Thessaloniki, Greece, *Democritus University of Thrace, Greece and 3**Hunting Federation of Sterea Hellas, Greece
Corresponding address Email: kkitikid@fmenr.duth.gr

ABSTRACT

Animals’ overlapping food chains influence the amount of energy – biomass that moves from one feeding level to the next. Dietary habits of red fox (Vulpes vulpes) and stone marten (Martes foina) were studied in central Greece, using microscopic stomach analysis. Frequency of occurrence (FO) and relative volume (RV) were quantified. In order to study food niche overlap between two carnivores, the classical Pianka’s index method and an alternative method of tree analysis were compared. Both methods showed a seasonal overlap, provided that RV was used in tree analysis as an influence variable.
Keywords: classification trees; diet; Martes foina; overlap; Vulpes vulpes.