Bird trapping techniques to capture wild birds include a wide range of techniques that have their origins in the hunting of birds for food. While hunting for food does not require birds to be caught alive, some trapping techniques capture birds without harming them and are of use in ornithology research. Wild birds may also be trapped for their display in captivity in zoological gardens or for keeping as a pet. Bird trapping was formerly unregulated, but to protect bird populations most countries have specific laws and regulations. Bird trapping techniques to capture wild birds include a wide range of techniques that have their origins in the hunting of birds for food. While hunting for food does not require birds to be caught alive, some trapping techniques capture birds without harming them and are of use in ornithology research. Wild birds may also be trapped for their display in captivity in zoological gardens or for keeping as a pet. Bird trapping was formerly unregulated, but to protect bird populations most countries have specific laws and regulations. Birds are lured into the vicinity of traps through the use of suitable habitat patches where the birds are known to visit. A specific location may be further modified by the provision of food, the use of decoy birds, the use of calls, or owls that may induce mobbing. Male birds of some species are used as decoys during the breeding seasons to challenge and beckon other males from nearby. Owls and their calls are often used to bring birds out of dense vegetations. The technique has also used by birdwatchers. Almost all traps involve the use of food, water or decoys to attract birds within range and a mechanism for restricting the movement, injuring or killing birds that come into range. Food, water, decoy birds and call playback may be used to bring birds to the trap. The use of chemical sprays on crops or food can have more widespread effects and are not usually included in trapping techniques although there are some capture techniques that make use of bait with stupefying agents. The mechanism can be physical and non-lethal like a noose that tightens around the leg or lethal like in deadfall traps. Lethal techniques have been used for the control of birds considered as pests or can be used in the capture of birds for food. Traps can vary in their design to capture individual birds or large flocks and are adapted according to the habitat and behaviour of the birds. Trapping is regulated in most countries and needs to be operated by trained research personnel and failure to follow precautions can lead to injury or death of birds.