A tranquillizer gun (also spelled tranquilizer gun or tranquilliser gun), capture gun or dart gun, is a non-lethal air gun often used for incapacitating animal targets via projectile injection of anesthetic chemicals usually referred as tranquilizers. These guns shoot darts with a hypodermic needle tip, filled with a dose of tranquilizer solution that is either sedative, comatosing or paralytic, which once injected will temporarily impair the target's physical function to a level that allows it to be approached and handled in an unresisting and thus safe manner. Tranquillizer guns have a long history of use to capture wildlife without risking serious injuries to both the hunter and the target. Tranquillizer darts can also be fired by crossbow or breath-powered blowgun.
For thousands of years various tribal peoples have used poisoned arrows (for example tipped with Curare), to incapacitate animals before killing them, but the modern tranquillizer gun was invented only in the 1950s by New Zealander Colin Murdoch. While working with colleagues who were studying introduced wild goat and deer populations in New Zealand, Murdoch had the idea that the animals would be much easier to catch, examine, and release if a dose of tranquillizer could be administered by projection from afar. Murdoch went on to develop a range of rifles, darts, and pistols that have had an enormous impact on the treatment and study of animals around the world.
The first remote drug delivery system was actually invented by scientists at the University of Georgia in the 1950s, and was the direct predecessor to the Cap-Chur equipment used worldwide for decades.