Impacts of road networks on brown bear (Ursus arctos) and mitigation measures

• Main Authors: Psaralexi, Maria, Ψαραλέξη, Μαρία
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Aristotle University Of Thessaloniki (AUTH) 2023
• Subjects: Καφέ αρκούδα; Οδικά δίκτυα; Τροχαία ατυχήματα; Επιπτώσεις οδικών δικτύων; Μέτρα; Brown bear; Transportation networks; Road effects; Animal vehicle collisions; Road ecology; Mitigation measures; Road permeability; Βιολογία; Φυσικές Επιστήμες; Διατήρηση της βιοποικιλότητας; Biological Sciences; Natural Sciences; Biodiversity Conservation; Ursus arctos
• Online Access: http://hdl.handle.net/10442/hedi/55170; https://doi.org/10.12681/eadd/55170

Road networks, with their multiple impacts on the landscape and wildlife, are considered one of the main drivers of biodiversity loss. The most important road effects on wildlife are the road-related mortality and the barrier effects, which may isolate certain sub-populations increasing their extinction risk. Large mammals are particularly vulnerable to road effects due to their wide-ranging movements and low reproductive rates. Road construction projects have always been promoters of development for humans, but their negative road effects on biodiversity should be minimized (Chapter I). The mitigation hierarchy (avoid, mitigate, restore, compensate) is now being recommended, aiming to achieve no net loss outcomes, or even net gain outcomes. Thus, during the past 20 years, more and more mitigation measures have been tested and adopted to mitigate road effects. The common practice is to deal with mitigation during road construction, and hence, manage road verges and adopt and adapt measures on the roadway from the start. The main two goals to achieve are animal-vehicle collision reduction and connectivity preservation. To this end, there are many available mitigation measures that cover a wide range of costs and effectiveness. Animal-vehicle collisions is the most profound road effect on wildlife and their reduction has been one of the main goals of mitigation strategies worldwide. In Greece, the most known animal vehicle collisions involve brown bears, and the outcome of bear-vehicle collisions usually results in human injury, extensive property damage and animal fatality. Thus, we investigated these collisions from 2005 to 2020 in northwestern Greece (Chapter II). We recorded 101 bear-vehicle collisions and identified four collision hotspots, where 58% of total collisions occurred. The number of collisions with bears seems to follow activity patterns and hence, most collisions occurred during mating and hyperphagia. They also happened during the night when animals are more active, and there are low conspicuity ...