Two models for assessing the prey mass of European ungulates from wolf scats

Among the prey of wolf Canis lupus Linnaeus, 1758, in many European regions, roe deer Capreolus capreolus, red deer Cervus elaphus and wild boar Sus scrofa are of primary significance. Up to now, these species were not represented in models which allow an estimation of the consumed biomass on the basis of wolf scats. To develop such formulae for roe deer, red deer and wild boar, we fed these species to 5 captive adult wolves of European origin. In 10 feeding trials, the wolves were fed 10 prey, whose body mass ranged from 15.3 to 118.5 kg. We related the body mass of the prey in accordance with Weaver (1993) to one collectable scat (Model 1: y = 0.00554 + 0.00457x) and, as it is difficult to define one unit scat, we alternatively related it to one meter length of scats (Model 2: y = 0.141 + 0.0487x). The Model I equation differed from both of Weaver's (1993) regressions, which he had calculated on the basis of his own feeding trials and on the basis of the summarised data of Floyd et al. (1978), Traves (1983) and Weaver (1993). Applying an equation gained through the European ungulates resulted in lower estimates of prey mass. Model 1 and Model 2 estimates were comparable in size.