That is a fantastic question. I absolutely agree that this is the cutting edge of protected area planning right now.
I just returned from the Galapagos Islands where that very idea is entertained. They had smaller protected areas that are now linked together, and they are talking to Colombia and Costa Rica to link corridors towards the Cocos and Malpelo islands' protected areas, which are used by a lot of the same species, many of them very much depleted and highly vulnerable to extinction, like whale sharks, for example.
This is an idea from terrestrial conservation that is now being applied in the marine conservation areas as well, in other countries—not yet in Canada.