The correct option is 1 and 3 only. India's Desert National Park, located primarily in the Jaisalmer and Barmer districts of Rajasthan, serves as a critical habitat for the Great Indian Bustard, one of the world's heaviest flying birds, which is critically endangered. While efforts are made to preserve biodiversity and wildlife, some human habitation and traditional practices still exist within or around the park, which makes statement 2 incorrect. Thus, the park is significant for conservation efforts and biodiversity, aligning with the UPSC focus on environmental conservation and sustainable management of natural resources.