A record 20 bears have been killed by vehicles in the Lake Tahoe area so far this year, including two struck last week on Highway 89 near the Truckee River.
Ann Byrant, executive director of the BEAR League, says the previous record was 19 bears hit in 2005. She says it's unusual to have so many deaths this early in the year.
One bear was hit and killed on Thursday while trying to cross the highway to reach the river between Truckee and Tahoe City.
Another was struck and injured on Wednesday.
A sheriff's deputy euthanized him because his wounds were too severe.
Bryant says more bears are coming down to the Truckee River or Lake Tahoe because mountain creeks and streams are drying up.
She says they don't know enough to stop and look both ways before they cross the road.
Bryant says drivers should pay attention to the sides of the roads and look for movement during the day, or reflecting eyes at night.
She says they typically don't move very fast.