Motorists who swerve to avoid deer, cattle and other large animals are almost as likely to end up in the emergency room as those who hit them, U.S. health officials said on Thursday.

An estimated 10,080 people are treated for non-fatal injuries each year from crashes that occur after a driver swerves or slows down to avoid large animals, according to a study by the Centers for Disease Control and Prevention.

The bulk of these injuries are a result of a car going off the road or hitting a tree, pole or guardrail, according to the CDC, which compiled 2001-2002 data from 66 emergency rooms across the nation.

In comparison, about 12,245 Americans are treated for non-fatal injuries after collisions with large animals.

Ann Dellinger, a CDC epidemiologist and one of the study’s authors, said drivers who come across animals on the roads should consider a number of factors, including road and weather conditions, before deciding whether to take evasive action.

“There are so many things that are going to impact each crash that it’s difficult to say how they would fall out if everybody did one thing,” Dellinger said.

Animal-related car crashes could be cut if drivers stayed alert and did not speed or drink and drive, according to the CDC. The Atlanta-based agency also said greater use of fences and underpasses could reduce the incidence of such accidents.

An estimated 247,000 car accidents involving animals, usually deer, are reported each year in the United States. About 200 people die as a result of these crashes.

Drivers, especially those in Wisconsin and other rural states with large deer populations, are advised to be aware of the times when deer are more likely to be crossing roads.

Crashes involving large animals are more likely to occur in October and November, the height of the fall deer-hunting, mating and migration season, and during early morning and at dusk.