Corusca fishermen were miners who mined Corusca gems in the upper atmosphere of Yavin. They would typically attach an energy purse seine or flexisteel cable net with a thick mesh to several space-capable one-man skiffs and one trawler. The trawler would be used to provide propulsion for the entire group. Meanwhile, the skiffs would keep the net steady.
To reduce the risk of being hit by Corusca gems, many Corusca fishermen would follow the paths of Yavin's floaters. Doing so considerably increased the safety of Corusca mining, but it also reduced the speed at which the fishermen could operate and the amount of gems that made it into their nets.
Since they were only operating in the upper atmosphere of Yavin, Corusca fishermen would only expect to catch smaller Corusca gems and dust, not the larger ones that were only present in the lower atmosphere. However, mining in the upper atmosphere was still considered worth the effort.