Every national wildlife refuge was created for a special purpose. Some were created to protect migratory birds, others to protect threatened or endangered species or unique habitats, while others fulfill another special purpose. All activities allowed on refuges must be evaluated to make sure each activity will not conflict with the reason the refuge was founded.

Sherburne serves as an inviolate sanctuary for migratory birds. The Migratory Bird Hunting and Conservation Act uses money from Duck Stamp sales to purchase refuge lands, and over 95% of the refuge was purchased using these funds. Many lands purchased with Duck Stamp funds were defined as inviolate sanctuaries. These lands, under most circumstances, must be at least partially closed to migratory bird hunting to allow birds a place of refuge and protection where they cannot be harmed..