Roads acts as barriers for wildlife and together with wildlife-vehicle collisions (WVC) they can threaten populations size and genetic diversity. Wildlife fences are a common measure to reduce WVC which can increase the barrier. Mitigation measures often used to increase landscape connectivity are fauna passages such as overpasses and underpasses that allow animals to cross the roads. These types of fauna passages are often very expensive and therefore it is of interest to find an alternative for roads that might not have the financial motivation to build such structures. This study examined the behaviour of animals in an at-grade fauna passage with an animal detection system in Sjödiken, Sweden, which was installed in 2019. A previous study of the fauna passage showed that roe deer spent a long time grazing in the entering zone and the road verge of the passage was therefore sanded. The aim of this study was to evaluate how the time in the passage changed after sanding as well as how it affected the crossing success of the animals. Results showed a decrease in time spent in the entering zone for roe deer, red deer and wild boar as well as a decrease in total time in passage for red deer and wild boar. Crossing success increased after sanding for roe deer, and red deer also showed a tendency to increased crossing success. Wild boars crossing success did not change but was high both before and after sand treatment.