Rather than move the conversation along from the friendly bears (black, grizzly or polar)* to really really nasty critters like wolverines . . . .

Short version.  Newfoundland had no chance whatsoever to remain a Dominion.  

It basically bankrupted itself with WWI debts on top of expenditures for the Newfoundland Railway across the island.  (Narrow gauge, across some "interesting" terrain, run until maybe 1970ish.)  The place was very poor except for local spots around mines or the like, some places little advanced since 1900 or so in terms of way of life and technology - and all of that linearly, and slowly, descended from 300 years of fishing.  Up until the 1960s it was at least a decade behind the rest of us, even poorest parts of Canada.  

The Nfld legislature basically up and quit in 1933, turning the Dominion back to the Crown as a colony.  It was then governed by an appointed Commission until it joined Canada in 1949.  WWII brought employment building bases, especially USAAF bases, and a lot of cash that had never been seen into peoples hands.  Postwar there was pressure for renewed independence (as had been agreed could be returned in 1933) but it led to various proposals and by a narrow margin, which some still consider fraudulent, a vote to join Canada.  

Even today, the province is a "have" province due to the offshore oil but is otherwise a weak and unbalanced economy and it continues to export people to the rest of the country.  There are weekly charter flights to the oil hot-spots in the west, to accommodate workers who live on da Rock with their families and fly west to work for a few weeks at a time -- kind of like going to sea on wooden ships in the old days.

*As for which bear is nastiest, one renowned expert responded, ignoring the smallish black bear: "Well, you can negotiate with a grizzly, but to a polar bear if it moves its food."