If you’re worried about car accidents caused by deer, you might want to look into bringing some cougars into town. As deer populations have grown, though, so have traffic accidents. To look at how cougars affected deer behavior, the researchers compared data selected from more than 500 cameras across the peninsula with data gathered from a year of car accidents that involved deer. Cougars “are ambush predators,” Suraci says: “They prefer these sort of edgy, moderately fragmented habitats—roads cutting through the forest or lower-density development, pushing up against a forested area.” These enabled the team to look at behavioral patterns of deer in areas where predators hadn’t been newly introduced and helped to rule out fewer accidents due to the decline in deer numbers caused by cougars hunting them.