I read this book in perhaps 5th grade (1975). An Inuit Girl lives with her mother but is either urged to leave or gets lost (set in Greenland?). She encounters a polar bear and is “adopted” by bear. The hardcover book jacket featured girl in traditional parka riding the bear, she has a spear I think.

Sounds suspiciously like East published in 2005, but this was long before that.  I remember her learning to fish.

Any assistance greatly appreciated.