Shark culling is the deliberate killing of sharks by government authorities, usually in response to one or more shark attacks. The term "shark control" is often used by governments when referring to culls. Shark culling has been criticized by environmentalists, conservationists and animal welfare advocates—they say killing sharks harms the marine ecosystem and is unethical. Government officials often cite public safety (attempting to reduce the risk of shark attacks) as a reason for culling. The impact of culling is also minor compared to bycatch with 50 million sharks caught each year by the commercial fishing industry.