This is the eighth annual report on California's roadkill -- hotspots and trends. We found a decline in mule deer roadkill, suggesting a decline in the statewide deer population. We also identified issues with the current methods for prioritizing where to act to benefit wildlife on state highways and highlight ways to reduce roadkill.

Using observations of reported traffic incidents and carcasses the Road Ecology Center has estimated the total annual cost of reported (large) wildlife-vehicle collisions for 2018 in California to be at least $232 million and the cost to society over the last 4 years to be >$1 billion. The cost is calculated using California Highway Patrol (CHP) reports of crashes with wildlife and US Department of Transportation equivalent values for different types of crashes (e.g., property damage vs. major injury).

Using observations of reported traffic incidents and carcasses the Road Ecology Center estimates the total annual cost (2017) of wildlife-vehicle conflict (WVC) in California to be at least $307 million, up 11% from 2016. The cost is calculated using CHP reports of crashes with wildlife and US Department of Transportation equivalent values for different types of crashes (e.g., property damage vs. major injury). The estimated cost could be as high as $600 million if accidents that are claimed to insurance companies (but un-reported to police) were included.

Using observations of reported traffic incidents and carcasses the Road Ecology Center estimates the total annual cost of wildlife-vehicle conflict (WVC) in California to be at least $276 million, up 20% from the year before. This report includes maps of WVC hotspots, discusses impacts to wildlife and people from WVC, and ranks highways in each Caltrans District for financial cost of WVC (spoiler, I-280 in District 4 is the costliest). Projects to reduce WVC can be the most effective of any safety project, with effectiveness often >90%.

Using data from the California Roadkill Observation System (http://wildlifecrossing.net/california), the Road Ecology Center has mapped stretches of highway that are likely to be hotspots for wildlife- vehicle collisions (WVC).