Abstract 325 – Factors affecting forest road use in Eurasian Brown Bears

David Blount, Mark Chynoweth, Josip Kusak, Cagan Sekercioglu

Of all anthropogenic disturbances, none are quite as ubiquitous as roads. Over 20% of all
Earth’s terrestrial landmass is located within 1 km of a road, and the remaining landmass
greatly fragmented (Ibisch et al. 2017). More developed continents, like Europe, have even
higher concentration of roads, with 50% of its land within 1.5km of a road (Torres et al., 2016).
Roads have been shown to be ecological traps for many carnivores, including brown bears,
offering food (Roever et al., 2008) and movement corridors (Roever, Boyce & Stenhouse 2010)
at a cost of increased mortality from cars and humans (Northrup et al. 2012). This relationship
is complex, and traffic volume may be more important than road density in determining how
bears use roads and their survival outcomes (Northrup et al. 2012). Roads with limited traffic
have actually been shown to be selected for in resource selection functions and used more
frequently (Northrup et al., 2012; Blount et al., in review). In this study we used 40 GPS collared
bears and camera traps on forest roads to understand what factors affect unpaved forest road
use in Eurasian brown bears in northeastern Türkiye. We measured brown bear activity across
the year using accelerometer data from GPS collars to understand when bears were active. We
then paired this data with a large camera trap array to understanding forest road use by bears
in relation to bear activity. Combining these techniques, we were able to understand when
bears use roads, how road use patterns change across seasons, and what factors may affect
forest road use. As brown bears colonize human populated areas across Europe, understanding
when and how bears use roads is vital to decreasing human caused mortality, and limiting
human-wildlife conflict.