What if the Reapers found a dying civilization?

The Reapers goals are to preserve sentient life, because the artificial intelligence the sentient species creates kills them all right? But what if the Reapers found a civilization on the verge of dying on there own planet?( example if the Hanar never met the Drell and they were stuck dying on their planet) Would the Reapers harvest them too or would they leave them be?