During the early 1960s, an international market for wild venison was established, and with no restrictions on hunting, market hunters established themselves in the rugged park country and used pack horses, jetboats and fixed wing aircraft to get the carcasses out to market. Experiments with shooting wild deer from helicopters were highly successful and a competitive industry was based on this technique. By the late 1970s, the deer population in Fiordland had been severely reduced, and combined with a flourishing deer farming industry this has reduced the impact of aerial hunting over the national park.