 Holt established a scientific oyster farming program at Quibray Bay, attempted to raise sheep on specially planted pastures of imported grass and dabbled in timber getting and even coal mining on the Kurnell peninsula.This work was done with the assistance of many employees including a number of Aboriginal people including William Rowley, a Gweagal man, who was also an enterprising local fisherman born at Towra Point.Despite Holt's efforts at Kurnell none of the enterprises were very successful and by 1881 he began subdividing the estate.