Captive pheasants Phasianus colchicus frequently practise cannibalism: this isn’t necessarily as gruesome as it sounds, but mostly consists of repetitive pecking or picking that opens wounds or results in the removal of toes. In chicks, toe and beak picking are common, while vent, wing and head picking more frequently occurs in older birds. Open, bleeding wounds (when visible) cause the birds to attack again, and they will keep attacking until the victim is fatally injured or killed. All gamebirds practise this sort of behaviour in captivity, but pheasants are by far the worst.
‘Outbreaks’ of cannibalism have been reported when young pheasants have been kept in over-crowded conditions. Boredom might contribute to the habit as much as over-crowding, so the best way of reducing its incidence is to give the birds stuff to do. Providing them with perches, lots of material to peck at (like hanging bales of straw, or naturally growing vegetation), and lots of space all helps to reduce the problem. It can be symptomatic of over-heating, so ventilation and temperature control need to be looked at when it occurs. But a few more solutions to the problem have been invented. Some are more objectionable than others. I’m not going to provide any moral perspective here; I’m merely giving you the information.
The least extreme methods involve fitting the birds with structures – rings (like that shown above) or blinders or ‘spectacles’ – that stop them pecking. Rings fit under the palate, over the tongue, and insert into both nostrils. The ring is not complete, and if fitted properly it doesn’t damage any of the bird’s soft tissues. It also shouldn’t hurt the bird, but it does prevent it from closing its jaws, and thereby stops it from forming a point that can be used to peck with. Different sized rings are available for chicks and adults. ‘Spectacles’ and blinders are a bit more complicated, more difficult to fit, and more of an obstacle to the bird’s behaviour and well-being (they sometimes snag on feeders and other structures). They fit on to the dorsal surface of the bill, sometimes attaching to the nostrils. A selection of blinders are shown here [from Ernst et al. (2007)].
By far the most extreme technique used in poultry management is beak trimming. The name makes it sounds less extreme that it is: it doesn’t involve shaving a few millimetres of keratin off the bill. Rather, about a third of the upper mandible is broken off. This can be done manually (with clippers of some sort; even nail clippers), or automatically with a machine like that shown here [image from here]. Because the beak tissue does grow back pretty quickly (like everything else in birds) trimming has to be repeated every 4-6 weeks. Lack of wear from an upper jaw tip sometimes leads the lower jaw tip to become over-long, so it has to be trimmed as well sometimes. I say that beak-trimming is ‘extreme’, but I think it’s practised pretty frequently in the poultry-rearing industry.
Quite why I got distracted by the world of pheasant cannibalism and management I’m not entirely sure, but I hope you found this interesting.
Ref – –
Ernst, R. A., Woodard, A. E. & Vohra, P. 2007. Raising game birds. ANR Publication 8155. University of California, Agricultural and Natural Resources (Oakland) [free pdf here].