Busy beavers are back at work on the Tule River Indian Reservation in the southern Sierra Nevada. Tule River Tribe members saw beavers depicted in their ancient pictographs and tribal elders could remember their presence long ago on the reservation, but before last week the land was barren of beavers and the ecosystem benefits of the crafty critter’s activities. Beavers are thought to be part of the solution as California faces challenges of climate change. The beavers released on the Tule River