Status and distribution of the lynx (Lynx lynx) in the Swiss Alps 2005–2009

Abstract

We evaluated the status of lynx in the Swiss Alps for the period 2005– 2009. Even though the number of lynx presence signs remained almost stable between the present (2,068 signs) and previous pentad (2,091), there was a 7.6% increase in the area occupied by the 5-km circular buffers around the confirmed lynx signs of presence over the five years period (12,637 km2 ). The north-western Swiss Alps (VI) remained the compartment with the highest number of chance observations. It was followed by compartments central Switzerland west (III) and north-eastern Switzerland (II). These sub-populations acted as source in the current pentad, as signs of reproduction were reported almost every year. The translocation to north-eastern Switzerland is still the only significant contribution to the spatial increase of the lynx range in the last 10 years in the Swiss Alps. The small and vulnerable north-eastern Switzerland lynx sub-population plays an important role for the Alpine population. There is hope that in the future this sub-population could act as stepping stone to the eastern Alps and together with individuals dispersing from the central Switzerland west (III) subpopulation would enable to found a new sub-population in central Switzerland east (IV). The status of the sub-population in the Valais (VII) is less clear. As only few signs of reproduction and mortalities were reported over the pentad, it acted more as sink than a source population. From the few signs of lynx presence reported in the remaining compartments (Grisons V, central Switzerland east IV and Ticino VIII) we concluded that only a few single lynx that did not yet establish the typical social organisation occur there. An occupancy-based population estimate from a parallel study resulted in about 111 (SE = 10) independent lynx for the period 2005–2009. This is higher than the 60–90 individuals estimated for the previous pentad.