Thereafter the Ngāi Tahu moved steadily southwards in a campaign of conquest, until after a little more than a generation they had subjugated the Ngāti Mamoe in most of the country of the east coast, as far south as Lake Waihola, south of the Otago peninsula. During this period, when many of the Ngāti Mamoe were a hunted people, some groups of them lived in the caves of the river gorges, as at Weka Pass, Opihi Gorge, and the Upper Waitaki. Drawings on the walls of these 'rock shelters' suggest their occupation. Nevertheless, there appears to have been considerable intermingling of the two tribes so that in later years, the Ngāti Mamoe lost their identity as a separate people.