Integrating sign surveys and telemetry data for estimating brown bear (Ursus arctos) density in the Romanian Carpathians

摘要: Accurate population size estimates are important information for sustainable wildlife management. The Romanian Carpathians harbor the largest brown bear (Ursus arctos) in Europe, yet current management relies on of density that lack statistical oversight and ignore uncertainty deriving from track surveys. In this study, we investigate an alternative approach to estimate using sign surveys along transects within a novel integration occupancy models home range methods. We performed repeated 2-km segments forest roads during three distinct seasons: spring 2011, fall-winter 2012, game units Natura 2000 site. estimated bears abundances number unique tracks observed per survey occasion via N-mixture hierarchical models, which account imperfect detection. To obtain densities, combined these with effective sampling area transects, is, as function median (± bootstrapped SE) core (5.58 ± 1.08 km2) based telemetry data 17 tracked 1-month periods overlapping our windows. Our analyses yielded average densities (and 95% confidence intervals) seasons of: 11.5 (7.8–15.3), 11.3 (7.4–15.2), 12.4 (8.6–16.3) individuals/100 km2. Across units, mean ranged between 7.5 14.8 individuals/100 km2. method incorporates multiple sources (e.g., area, detection) density, but inference fundamentally unmarked individuals only. While useful temporary monitor bears, urge implementing DNA capture–recapture methods regionally inform recommend increasing resources GPS collars improve area.