At one point, the mighty bald eagle was about to disappear from the Great Smoky Mountains National Park, America's most visited national park. That's when the theme park Dollywood stepped in and began a captive breeding program and successfully returned the bald eagle to the Smokies. There is an aviary at Dollywood that's home to bald eagles that can't be released into the wild, and also a show showing off several different birds of prey. If it wasn't for Dollywood investing their time and money into returning this majestic bird to the Smokies, the bald eagle would never soar over the Smoky Mountains. Yes Dollywood is not a railroad, but they're doing the same thing as Network Rail: preventing the demise of a bird of prey from disappearing from their native habitat.
P.S. One of their roller coasters, Wild Eagle, is themed to the bald eagle, complete with the bodies of the individual cars painted to look like bald eagles. They also have a large, metal sculpture of a bald eagle sitting outside the entrance to Wild Eagle and, over time, the metal of the sculpture will slowly rust, turning brown, just like the feathers of the bald eagle.