YOSEMITE — Highway 140 between Crane Creek and Parkline in El Portal has become thick with thousands of California tortoiseshell butterflies, say officials in Yosemite National Park. This species emerges in spectacular numbers in some years and is thought to be the source of Mariposa County’s name, which is Spanish for butterfly.
This particular corridor where butterflies converge can become a killing zone when vehicles move through the area too quickly. Officials ask that visitors please help minimize the number of butterflies killed by reducing your speed when you encounter their swarms. At 25 miles per hour, the butterflies are more likely to follow the slipstream around your car and emerge unscathed.
At higher speeds the butterflies smash into car windshields and grills, leaving windrows of dead butterflies along the road. This is also a risk to the birds that come to feast on the dead butterflies.
Please help preserve the butterflies, and this unique display of nature’s abundance. Slow to 25 miles per hour, and keep the butterflies alive.
C. Lee-Roney, NPS