EN
Patterns of lynx Lynx lynx {Linnaeus, 1758) predation on ungulates were studied in the Polish part of Białowieża Primeval Forest (580 km ) from scats and prey remains of iynx between 1985-1996, and radiotracking of IS lynx between 1991-1996, Cervids were the main prey and constituted 90% of food biomass consumed (analysis of faeces) and 84% of prey killed. Roe deer Capreotus capreolus was positively selected by all lynx (though stronger by females and subadults than by adult males). Fawns and adult roe deer of both sexes were preyed on in proportion to their abundance in the population. Red deer Ceruus elaphus was taken less often than would have been expected at random, and fawns were positively selected by lynx. On average, lynx spent 76 h (3.2 days) feeding on a killed deer (from 38 h in a female with 3 kittens to 105 h in single adult females). Mean searching time (ie time from leaving the remains of one deer to killing another one) was 52 h (2.2 days); from 10 h in a female with 3 young to 104 h in subadults. Thus, the average kill rate by lynx was one deer per 5.4 days. Predation impact of lynx population on roe and red deer was estimated in 1991-1996, when recorded numbers were 288-492 roe deer and 359-607 red deer per 100 km" in late winter (March), and 501-820 roe deer and 514-858 red deer per 100 km" in spring (May/June). During that period densities of deer declined markedly due to deliberately elevated hunting harvest by forestry personnel, aimed at reduction of game damage to silviculture. Densities of adult lynx were little variable (2.4-3.2 inds/100 km2), but reproduction rate strongly varied in response to deer decline, from 0.67 juv/adult lynx in 1991/92 to 0.25 juv/adult lynx in 1995/96. Annually, lynx population killed 110-169 roe deer/100 km2, which constituted 21-36% of spring (seasonally highest) numbers of roe deer. Lynx predation was the most important factor of roe deer mortality. Furthermore, lynx population took 42-70 red deer/100 km2 annually, which constituted 6-13% of spring number of red deer. In red deer mortality, lynx predation played an inferior role to hunting harvest and wolf predation.