Prey spectrum, prey preference and consumption rates of Eurasian lynx in the Swiss Jura Mountains

We examined 617 kills made by radio-tracked Eurasian lynx Lynx lynx (Linnae us, 1758) from March 1988 to May 1998 to assess prey spectrum, preference, and food consumption rates in the Swiss Jura Mountains. Roe deer Capreolus capreolus and chamois Rupicapra rupicapra were the main prey (69 and 22%, r espectively), followed by red fox Vulpes vulpes, brown hare Lepus europaeus , domestic cat Felis catus, wild cat Felis sylvestris, marmot Marmota marmo ta, pine marten Martes martes, capercaillie Tetrao urogallus, and badger Me les meles. Lynx fed on an ungulate prey from 1 to 7 days, depending on the prey category. The consumption rates of males, of females alone, and of fem ales with kittens varied from 3.2 to 4.9 kg per night, with an increasing t rend as the kittens grew older. Including the days when lynx had no kill (s earching time) lynx consumed 2 +/- 0.9 kg per night. The mean searching tim e was 1.5-2 days for females, depending on the season and the number of kit tens, and 2.5 days for males. The mean interval between consecutive kills w as 5.9 for males and 5.2 days for females, respectively. At 38% of carcasse s the presence of one or several scavengers (red fox, raven Corvus corax or both) was detected. Although 69% of the kills were roe deer and only 22% c hamois, we hypothesise that in the forests of the Jura Mountains chamois ar e more vulnerable to lynx predation than roe deer, as chamois had a slightl y higher preference index (0.59) than roe deer (0.41), based on rough estim ates of the two ungulate populations in the study area.