You shall pass!

1. You shall pass! A mechanistic evaluation of mitigation efforts in road ecology Christer Moe Rolandsen, Bram van Moort­er, Manuela Panzacchi, Erling J. Solberg, Ole Roer

2. Background Moose-vehicle accidents Photo: Tore Sannum, NTB scanpix

3. Background Moose-vehicle accidents Photo: Tore Sannum, NTB scanpix

4. Moose vehicle accidents • The majority of accidents in winter (Nov. – Feb.)

5. Introduction • Study movement near roads and road crossing by a large mammal • On roads with fences and crossing structures, and on unfenced roads with varying traffic intensity • Use and effectiveness • We have no controls when only looking at rate of use (e.g. with cameras) • E.g. effects of local population density • By looking at variation in individual behaviour (GPS marked moose) with step selection functions (SSF) each animal becomes its own control Photo: Christer Moe Rolandsen / Øystein Os

6. Study area Photo: Ole Roer

7. Study area

8. Study area

9. Study area Photo: Ole Roer Photo: Ole Roer Photo: Ole Roer Photo: Ole Roer

10. Stepselectionfunctions • 55 GPS marked moose Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

11. Stepselectionfunctions • 55 GPS marked moose • 448 061 positions Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

12. Stepselectionfunctions • 10 random steps for every observed step • 2 hour interval • Covariates • Land cover • Forest ageclass • Traffic volume • Slope • Roads / railways • Crossing structures • Fences • Water Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

13. Stepselectionfunctions • Predicted from the SSF • Friction map Low– medium - high Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

14. Stepselectionfunctions • Road avoidance • High (20000 AADT), medium (1500 AADT), low (private roads) • Stronger avoidance with increasing traffic volume • No obvious threshold Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

15. Stepselectionfunctions • Crossing structures • Wildlife, multi-use, grey • Highest probability that moose use wildlife crossing structures (compared to a road without fence) Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

16. Stepselectionfunctions • What is the optimal distance between crossing structures? • Compared to crossing a road without fences • If wildlife crossing structures: 1.4 kilometer - If the goal is to compensate for the fence from a moose persepctive! Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

17. Discussion • Allows us to get quantitative estimates on mitigation effects where we previously most often was left with expert opinions • First results based on SSF • Should be validated/compared with similar studies elsewhere and with other species • Suggests that we need dedicated wildlife crossings! • Estimate on the required distance between structures (given a certain goal) • No threshold regarding the effect of traffic volume • Results from the friction map is also useful for connectivity on a larger scale - least cost path, random walk (circuitscape) • Contribute to maintain connectivity and safety for animals and people Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

18. Discussion • Future studies • Why is multi-use less good? • Too little cover? • Physical properties? - Size, over- or underpass, etc. • Other seasons and variation during the 24-hour period Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os

19. Thankyou! Photo: Ole Roer Photo: Christer Moe Rolandsen / Øystein Os