 These programs exist to reduce the risk of shark attacks — however, environmentalists say that they do not reduce the risk of shark attacks; they also say that shark culling harms the marine ecosystem.Shark culling currently occurs in New South Wales, Queensland, KwaZulu-Natal and Réunion.Queensland's "shark control" program killed roughly 50,000 sharks between 1962 and 2018 — Queensland's program uses lethal devices such as shark nets and drum lines.