In recent years, the total quantity of abalone produced on farms worldwide has increased significantly, although abalone fisheries have declined. Production from fisheries has decreased from almost 20,000 metric tonnes (mt) in the 1970s to only about 6,500 mt in 2016/17. Over the same period, farm production has increased from negligible quantities in the 1970s to about 160,662 mt in 2016/17, the vast majority being produced in China (139,697 mt) and South Korea (16,042 mt). Illegal exploitation, particularly in South Africa, Australia, New Zealand, and California, is still a major problem reaching an estimated 7,000 mt in the 2016/17 period. A positive development that partially counteracts the illegal exploitation has been the establishment of restoration and ranching operations in various countries around the world. Taking all sources of abalone into account (fished, farmed, and illegal), it is estimated that in 2017, the total availability of abalone to the world market was 174,162 mt.