Grenade harpoons are explosive devices that are attached to harpoons, which are used to hunt marine creatures such as whales and sharks. These harpoons are designed to pierce through the thick skin of the target and once attached, the grenade is triggered, exploding and causing significant damage to the animal. The use of grenade harpoons has been highly controversial, as it is viewed as a cruel and inhumane method of hunting. Many countries have banned this practice, and alternative methods such as non-lethal tagging and tracking have been developed.