Population dynamics (1869–1994), demography, and home ranges of the lynx in Bialowieza Primeval Forest (Poland and Belarus)

Population dynamics, demography and home ranges of the Eurasian lynx Lynx lynx were studied in Bialowiez?a Primeval Forest (BPF, 1250 km²), the best preserved mixed and deciduous forest in the lowlands of Europe; 40% of BPF area belongs to Poland and 60/0 to the Belarus Republic. Results of radiotelemetry of lynx (1991–1994) were combined with the Polish and Belarussian game departments' inventories of lynx numbers (1946–1994), archival hunting statistics (1869–1989), observations and snowtracking of lynx. In 1991–1994, 12 lynx were radiocollared. Their home ranges covered from SO to 246 km² (mean 147 km²), depending largely on the time the lynx was radiotracked. During a given period, i.e. the autumn-winter seasons (I October-30 April), the home ranges were largest in adult males (90–148 km²), then in adult females (82–108 km²), and smallest in subadult lynxes (39–55 km²). Home ranges overlapped extensively. In winters 1992/93 and 1993/94, 21 and 29 lynxes, respectively, were recorded by the mapping of radiotracked and snowtracked individuals in the Polish part of BPF. Of them, 45/11 were ‘transborder’ individuals utilising both Polish and Belarussian pits of BPF. Winter densities were c. 3 adult lynx 100 km^-2 and 5 lynx 100 km^-2 if kittens were included. Adult males formed, on average, 29% and reproducing females 23% of all lynx. Subadults and kittens constituted, respectively, 12% and 35% of the population. Sex ratio was 1:1. During the first 3 months of kittens' life, on average 3.3 kittens/mother were recorded; only 1.6 young/mother survived till independence. Mortality of kittens was at least 48%, and the rate of mortality was highest during the early stage of kittens' life. Mean annual reproduction rate of lynx population was 0.59. In the protected population, annual mortality rate of subadult and adult lynx was on average 0.37. Poaching was the most important factor contributing 71% to the total annual mortality rate. During the last 125 years (1869–1994), three periods with relatively low harvest of lynx by man and thus with fairly natural functioning of lynx population, were recorded: before 1875 (density 2–3 lynx 100 km^-2), in 1920–1959 (4–6 lynx 100 km^-2) and after 1970 (2–5 lynx 100 km^-2). The levels of lynx densities were most probably determined by the varying abundance of roe deer Capreolus capreolus and red deer Cervta elaphus (lynx's main prey) in the ungulate community in BPF. Two periods of near extermination of lynx occurred (1890–1914 and 1960–1970), both caused by deliberate persecution of lynx. As soon as persecution was abandoned, lynx population recovered rapidly, mainly due to immigration from vast continuous forests in the east and north-east. Review of the long-term data on lynx dynamics in the Palaearctic revealed that in the Far North-East (Yakutia), the 10-year cycles of lynx and the blue hare Lupus timidus, its main prey, were recorded. Towards west, the cycle period becomes shorter (5–6 years in the Komi region). In the SW regions of the Palaearctic, where lynx relies on ungulates, lynx numbers are more stable but, periodically, also more aflected by man.