Opponents of the plan include the Friends of Big Bear Valley, the nonprofit group behind the live stream of beloved bald eagles Jackie and Shadow.
The 62-acre Moon Camp development, including 50 residential properties, would be visible from their nest camera.
"Some of the potential devastating impacts this development would have include: the proposed site is documented foraging habitat for our world famous bald eagles, numerous other avian and water fowl species," said Crestline resident Pamela Blackwolf during a San Bernardino County Board of Supervisors meeting on Tuesday.
"The proposed site will cause the destruction of endangered plant species and habitats. The proposed site has a completely inadequate fire evacuation plan."
The board voted unanimously to approve the development's tentative tract map and environmental impact report.