For more than 150 years Western State Hospital, just south of Tacoma, has cared for the state's most vulnerable psychiatric patients. A clinical setting, that unbeknown to many, also served as a natural habitat for a small, flying, federally protected species of animal. A symbiotic relationship that can reveal beautiful, if not unexpected pairings. “Bats are living in the rooftops of people’s homes, in their trees all over Washington,” said Michelle Tirhi, a wildlife biologist for the Washington Department of Fish and Wildlife. “They’re trying to provide habitat and maintain habitat for animals and allow animals to co-exist but they’re also trying to run a hospital that has patients in it,” Tirhi said.