A dark stain on Highway 385 tells the story of an unsettling trend in Wind Cave National Park.
A bison bull, cow and calf were all killed here last week when they were hit by a commercial truck just inside the park's south entrance. That made 14 bison killed this year by vehicles, compared to an average of three.
Park officials are especially concerned because six bison, including three last week alone, have been killed since early October. And park spokesman Tom Farrell says there's a pretty simple explanation.
"It's just driving too fast. People, you know, we have a low speed limit in the park. We have 45 miles an hour. But sometimes even that's too fast," Farrell said. "I mean, when I'm driving home at night, when I'm coming up on this curve, I drive slow just because I know there's a good chance that the bison are down at the south entrance."
All drivers should operate that way in the park, Farrell says. Park officials are trying to help slow things down and reduce animal collisions with warning signs, hazing wildlife away from dangerous roads and writing tickets to speeders. They will also consider stronger penalties, in certain cases.
"We investigate every accident. And if it's determined that the driver was at negligent, driving too fast or perhaps under the influence, we'll seek restitution for the cost of the bison," Farrell said.
They're valuable animals, after all, in a place where wildlife is special.
And Farrell said it isn't just bison he worries about. So far this year, motorists involved in accidents with bison in the park have escaped injury. And park officials hope to keep it that way, while protecting their bison herd.
"We've been very lucky so far that we haven't had any injuries to people," Farrell said. "But that's obviously a concern for us. We're here to protect the driver coming through the park and also our unique wildlife."