“She never left her cub,” said a Yosemite National Park ranger, heartbroken, after she witnessed a mother bear remain for hours with her lifeless baby who had been hit by a car on a park road in the summer of 2021.
adly, dozens of bears are hit, and sometimes killed, on park roads each year. Vehicle strikes are now one of the leading causes of death for bears in Yosemite. The park has posted warning signs at hot spot collision areas, attempting to compel visitors to slow down for the wildlife, typically to no avail.
And as visitation increases, the chance of a bear being hit by a vehicle also typically increases, according to my analysis of visitation trends and bear collisions. Keep adding more cars, and you’ll likely be causing the death of more bears.
I thought of that mother bear, standing over her dead cub for hours — and of the 28 bears hit and six killed by cars in the park in 2025 — after Yosemite Superintendent Ray McPadden told several news outlets that there was “zero evidence” that crowds impact the ecosystem or landscape in “any consequential way.” He was saying it as a justification for the recent removal of the park’s reservation system.
As someone who has spent the past 30 years documenting and studying Yosemite’s remarkable wildlife, I was astounded by the claim of “zero evidence.” I have witnessed it firsthand. And decades of park research and rigorous planning efforts demonstrate that there is substantial evidence that overcrowding in Yosemite has a profound impact on the park — and the bears and other wildlife that call it home.