Persistent and organized resistance? Not even the Native Americans and First Nations could manage that. There were a couple attempts to organize that were cut tragically short. I wouldn’t expect whales to be better at this than humans.
edit Specifically La Noche Triste. It was only after small pox killed about 40% of the population leaving most of the remainder to deal with disease caused sever disfigurement, disability, senility and starvation that the spanish really began to gain the upper hand.
Seriously, outside of efforts by Tecumseh and his brother Tenskwatawa, and the way-too-late Ghost Dance movement, intertribal unity efforts weren't really there. They won many, many battles against Europeans, but could not strategize to win a long war. Thus, disorganized and sporadic resistance.
Sure, disease made the conquest possible. And it's not a values judgement. It's just the old tale, divide and conquer.
It does rather sound like a value judgement when you bring it up the way you have.